Can't free memory from 2D dynamical array - c

I am having problem with freeing my memory. I did this many times, and it was working fine. Now, it just stops working (no error, anything, just freeze).
How my code looks like:
void args(int argc, char** argv, int *n, int *m, int **matrix, char name[20])
{
int firstIter = TRUE;
int x;
char op;
int** second;
second = NULL;
op = argv[1][0];
for (x = 2; x < argc; x++)
{
if (!firstIter)
{
setName(name, argv[x]);
loadMatrix(*m, *n, second, *name);
opMatrix(*m, *n, matrix, second, &*matrix, op);
}
else
{
setName(name, argv[x]);
loadSizeMatrix(n, m, name);
matrix = (int **)malloc(*n * sizeof(int*));
for (int i = 0; i < *n; i++) {
matrix[i] = (int *)malloc(*m * sizeof(int));
}
second = (int **)malloc(*n * sizeof(int*));
for (int i = 0; i < *n; i++) {
second[i] = (int *)malloc(*m * sizeof(int));
}
loadMatrix(*m, *n, matrix, *name);
firstIter = FALSE;
}
}
printMatrix(*m, *n, matrix);
for (int i = 0; i < *n; i++) {
free(second[i]);
}
free(second[0]); //doesnt work too, and yes, there are data
free(second);
}
second is being filled like this (loadMatrix):
for (int c = 0; c < radky; c++) {
for (int d = 0; d < sloupce; d++) {
fscanf(fp, "%i", &second[c][d]);
// printf("%i", matice[c][d]); // dump
}
}
How can I solve this error?
my full code
#include <stdio.h>
#include <malloc.h>
#include <stdlib.h>
#include <ctype.h> //tolower
#include <string.h>
#define TRUE 1
#define FALSE !TRUE
/* konstanty */
const enum {
MAX_DELKA_SOUBORU = 10000,
MAX_SOUBOR = 20
};
const enum {
SOUBOR_NENALEZEN = 1,
SPATNE_ARGUMENTY = 2,
LIMIT_NAZEV_SOUBOR = 3,
SPATNY_OP = 4
};
void error(int type);
void zpracovaniArgumentu(int argc, char** argv, char(*nazevSouboru)[MAX_SOUBOR], char(*nazevVystupni)[MAX_SOUBOR], int *n, int *m, int **matice);
void setNazevSouboru(char(*nazev)[MAX_SOUBOR], char *argument);
void vypisMatice(int radky, int sloupce, int **matice);
int nacteniMaticeZeSouboru(int radky, int sloupce, int **matice, char nazev[MAX_SOUBOR]);
int nacteniVelikostiMatice(int *n, int *m, char nazev[MAX_SOUBOR]);
int operaceMatic(int radky, int sloupce, int **prvni, int **druha, int **vysledek, char op);
int main(int argc, char** argv)
{
int n, m; // n = sloupce, m = radky pro prvni matici
int** first;
char nazevSouboru[MAX_SOUBOR], nazevVystupni[MAX_SOUBOR];
char op;
first = NULL;
zpracovaniArgumentu(argc, argv, &nazevSouboru, &nazevVystupni, &n, &m, &*first);
/* for (int i = 0; i < m; i++) {
free(first[i]);
} */
free(first);
system("pause");
return 0;
}
void error(int type)
{
switch (type)
{
case SOUBOR_NENALEZEN: printf("Soubor nenalezen!");
break;
case SPATNE_ARGUMENTY: printf("Program spustte s argumenty [nazev souboru] *[nazev vystupniho souboru]*.\n");
break;
case MAX_DELKA_SOUBORU: printf("Prekrocen maximalni limit delky nazvu souboru (%i).\n", MAX_SOUBOR);
break;
case SPATNY_OP: printf("Program spustte s argumenty [nazev souboru] *[nazev vystupniho souboru]*.\n");
break;
default: printf("Nastala chyba!");
break;
}
system("pause");
exit(type);
}
void zpracovaniArgumentu(int argc, char** argv, char(*nazevSouboru)[MAX_SOUBOR], char(*nazevVystupni)[MAX_SOUBOR], int *n, int *m, int **matice)
{
int firstIter = TRUE;
int doSouboru = FALSE;
int x;
char op;
int** second;
second = NULL;
op = argv[1][0];
for (x = 2; x < argc; x++)
{
if (!firstIter)
{
setNazevSouboru(nazevSouboru, argv[x]);
nacteniMaticeZeSouboru(*m, *n, &*second, *nazevSouboru);
operaceMatic(*m, *n, matice, &*second, &*matice, op);
}
else if (argv[x][0] == '-')
{
switch (argv[x][1])
{
case 'n': doSouboru = TRUE;
break;
default: error(SPATNE_ARGUMENTY);
break;
}
}
else if (doSouboru)
{
setNazevSouboru(nazevVystupni, argv[x]);
}
else
{
setNazevSouboru(nazevSouboru, argv[x]);
nacteniVelikostiMatice(n, m, *nazevSouboru);
matice = (int **)malloc(*n * sizeof(int*));
for (int i = 0; i < *n; i++) {
matice[i] = (int *)malloc(*m * sizeof(int));
}
second = (int **)malloc(*n * sizeof(int*));
for (int i = 0; i < *n; i++) {
second[i] = (int *)malloc(*m * sizeof(int));
}
nacteniMaticeZeSouboru(*m, *n, &*matice, *nazevSouboru);
firstIter = FALSE;
}
}
vypisMatice(*m, *n, matice);
for (int i = 0; i < *n; i++) {
printf("%i",second[i]);
free(second[i]);
}
free(second);
}
void setNazevSouboru(char(*nazev)[MAX_SOUBOR], char *argument)
{
strcpy(*nazev, argument);
strcat(*nazev, ".txt"); //nazev souboru
}
int nacteniVelikostiMatice(int *n, int *m, char nazev[MAX_SOUBOR])
{
FILE *fp = fopen(nazev, "r"); // načtení souboru
int c;
int radky = 1;
int sloupce = 0;
if (!fp)
{
error(SOUBOR_NENALEZEN);
exit(2);
}
else
{
while ((c = fgetc(fp)) != EOF)
{
//tolower(c);
if (c == '\n')
{
radky++;
}
else if ((isdigit(c)) && (radky == 1))
{
sloupce++;
}
}
}
fclose(fp);
*n = sloupce;
*m = radky;
return 0;
}
int nacteniMaticeZeSouboru(int radky, int sloupce, int **matice, char nazev[MAX_SOUBOR])
{
int x;
FILE *fp = fopen(nazev, "r"); // načtení souboru
if (!fp)
{
error(SOUBOR_NENALEZEN);
exit(2);
}
else
{
for (int c = 0; c < radky; c++) {
for (int d = 0; d < sloupce; d++) {
fscanf(fp, "%i", &matice[c][d]);
// printf("%i", matice[c][d]); // dump
}
}
}
fclose(fp);
return 0;
}
int operaceMatic(int radky, int sloupce, int **prvni, int **druha, int **vysledek, char op)
{
int vysledekClip[10][10];
for (int c = 0; c < radky; c++) {
for (int d = 0; d < sloupce; d++) {
switch (op) {
case '+': vysledekClip[c][d] = prvni[c][d] + druha[c][d];
vysledek[c][d] = vysledekClip[c][d];
break;
case '-': vysledekClip[c][d] = prvni[c][d] - druha[c][d];
vysledek[c][d] = vysledekClip[c][d];
break;
case '/': vysledekClip[c][d] = prvni[c][d] / druha[c][d];
vysledek[c][d] = vysledekClip[c][d];
break;
case '%': vysledekClip[c][d] = prvni[c][d] % druha[c][d];
vysledek[c][d] = vysledekClip[c][d];
break;
case '*': vysledekClip[c][d] = prvni[c][d] * druha[c][d];
vysledek[c][d] = vysledekClip[c][d];
break;
default: error(SPATNY_OP);
break;
}
vysledek[c][d] = vysledekClip[c][d];
}
}
return 0;
}
void vypisMatice(int radky, int sloupce, int **matice)
{
int c;
int d;
for (c = 0; c < radky; c++) {
for (d = 0; d < sloupce; d++) {
printf("%i\t", matice[c][d]);
} printf("\n");
}
}
void vypisMaticeDoSouboru(int radky, int sloupce, int **matice, char nazevSouboru[MAX_DELKA_SOUBORU])
{
int c;
int d;
for (c = 0; c < radky; c++) {
for (d = 0; d < sloupce; d++) {
printf("%i\t", matice[c][d]);
} printf("\n");
}
}

You have a problem with the 'second' array. You allocate an array of *n pointers to int but fill *m elements in that array:
second = (int **) malloc(*n * sizeof(int*));<p>
for (int i = 0; i < *m; i++) {

Related

Is there a way to combine two different strings alphabetically using stack in C?

Here is the program:
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
char *stack;
int stackindex = 0;
int push(char in){
if (stack==NULL) {
stack = (char *) malloc (sizeof(char));
}
else {
stack = (char *) realloc(stack, sizeof(char)* ++stackindex);
}
stack[stackindex] = in;
return 1;
}
char pop(){
return stack[stackindex--];
}
void show() {
for (int i=stackindex; i>=0;i--) {
printf("%c", pop());
}
}
int main(int argc, char**argv) {
for (int i = 1; i < argc; i++) {
int k = strlen(argv[i]);
int j;
for (int j = 0; j < k ; j++) {
char in = argv [i] [j];
push( in );
}
for (j = i; j < k; j++){
char temp;
if (stack[i] > stack[j]) {
temp = stack[j];
stack[j] = stack[i];
stack[i] = temp;
}
if (i, argc-1) push(' ');
}
show();
return 0;
}
}
I've been trying to make an output from the string "im loving" alphabetically in descending order (ASCII based) using command line arguments like this: vonmliig, but the output was "m i" instead.
Looks like you are trying to sort as you build the stack. I would build the stack first, then sort.
int main(int argc, char**argv)
{
if (argc >= 3) {
// Build stack
for (int i = 1; i < argc; i++) {
int k = strlen(argv[i]);
for (int j = 0; j < k ; j++) {
push(argv[i][j]);
}
}
// Sort
for (int i = 0; i < stackindex; i++) {
for (int j = i; j < stackindex; j++){
if (stack[i] > stack[j]) {
char temp = stack[j];
stack[j] = stack[i];
stack[i] = temp;
}
}
}
show();
}
return 0;
}
Also, there is an error in the handling of stackindex in push().
int push(char in)
{
char *temp = realloc(stack, stackindex + 1);
if (!temp) {
// Handle error
return -1;
}
stack = temp;
stack[stackindex++] = in;
return 1;
}
char pop()
{
if (stackindex) return stack[--stackindex];
else return 0;
}
void show()
{
do {
printf("%c", pop());
} while (stackindex);
}

I am trying to solve a special travelling salesman problem with mpi and c

#include <stdio.h>
#include <stdlib.h>
#include <limits.h>
#include <string.h>
#include <mpi.h>
#define MaxSize 50
typedef int ElementType;
typedef int Position;
typedef int Status;
typedef struct SeqStack
{
ElementType Data[MaxSize];
Position Top;
int (*Push)(struct SeqStack *L);
int (*Pop)(struct SeqStack *L , int e);
int (*isEmpty)(struct SeqStack s);
Status (*isFull)(struct SeqStack s);
}SeqStack;
int Push(SeqStack *L)
{
if(L->Top == 0)
{
return 0;
}
printf("%d ",L->Data[--L->Top]);
return 1;
}
int Pop(SeqStack *L , int e)
{
if(L->Top==MaxSize -1)
{
return 0;
}
L->Data[L->Top++] = e;
return 1;
}
int isEmpty(SeqStack s)
{
if(s.Top != 0)
{
return 1;
}
return 0;
}
Status isFull(SeqStack s)
{
if(s.Top != MaxSize -1)
{
return 1;
}
return 0;
}
int global_max;
int ans = INT_MAX;
void *tsp(int Dis[global_max][global_max],int v[],int N,int count,int currPos,int cost,int sum,int* result,int temp[],int make_log){
temp[0]=1;
//int mode;
//printf("count:%d\n",count);
if(count == N&&Dis[currPos][1]>0){
//printf("Ans:%d,cost:%d\n",ans,cost);
if(make_log == 1){
char str[100]={'\0'};
char output[100]={'\0'};
//printf("Ans:%d,cost:%d\n",ans,cost);
FILE *log;
for(int i=0; i<N;i++){
if (i!=N-1){
sprintf(str,"%d",temp[i]);
strcat(output,str);
strcat(output,",");
}else{
sprintf(str,"%d",temp[i]);
strcat(output,str);
strcat(output,"=");
}
}
sprintf(str,"%d",cost);
strcat(output,str);
strcat(output,"\n");
log=fopen("log.txt","a");
fputs(output,log);
fclose(log);
}
if(sum> cost){
sum = cost;
ans = cost;
//printf("every ans is %d\n\n\n\n",ans);
for (int i=0;i<N;i++){
//printf("temp[%d]=%d,",i,temp[i]);
result[i]=temp[i];
//printf("result[%d]=%d,",i,result[i]);
}
}
//ans = min(ans,cost + Dis[1][currPos]);
return result;
}
for (int i = 1;i<N+1;i++){
//printf("!!!!!!! v[%d] = %d\n",i,v[i]);
if(v[i]==0&&Dis[currPos][i]>0){
//printf("cost + Dis: %d + %d\n",cost,Dis[currPos][i]);
if(cost + Dis[currPos][i] <= ans||count==N-1){
v[i] = 1;
temp[count] = i;
//printf("\ntemp[%d] = %d\n",count,temp[count]);
//printf("currPos:%d,i:%d,count:%d\n",currPos,i,count);
//printf("Ans:%d,cost:%d\n",ans,cost);
result = tsp(Dis,v,N,count + 1,i,cost + Dis[currPos][i],sum,result,temp,make_log);
//mode = 0;
v[i]= 0;
if(count==1){
for(int j = 2;j<N+1;j++){
v[j]= 0;
}
}
}else{
//printf("currPos:%d,i:%d,count:%d\n",currPos,i,count);
temp[count] = i;
for (int k = N-1;k>count;k--){
temp[k] = 0;
}
int v_copy[N];
for (int o = 1;o<N+1;o++){
v_copy[o] = v[o];
// if(currPos==3&&i==4){
// printf("v_copy[%d] = %d//",o,v_copy[o]);
// }
}
for(int j = 2;j< N + 1;j++){
if(v[j]==0){
v[j] = 1;
}
}
result = tsp(Dis,v,N,N,N,cost + Dis[currPos][i],sum,result,temp,make_log);
//printf("Fuck currpos:%d\n",currPos);
for (int o = 1;o<N+1;o++){
v[o] = v_copy[o];
// if(currPos==3&&i==2){
// printf("v[%d] = %d//",o,v[o]);
// }
}
if(count==1){
for(int j = 2;j<N+1;j++){
v[j]= 0;
}
}
}
}
}
return result;
};
void change(int n){
global_max = n;
};
int main(int argc, char const *argv[])
{
int N;
int size = 1;
int count = 1;
int log = 0;
int nthreads,my_rank;
MPI_Init(&argc, &argv);
MPI_Comm_size(MPI_COMM_WORLD, &nthreads);
MPI_Comm_rank(MPI_COMM_WORLD, &my_rank);
if(argc > 2){
log = 1;
}
char x[100] = {0};
char filename[100] = {};
strcat(filename,argv[1]);
strcat(filename,".txt");
//printf("%s\n",filename);
FILE *fp=fopen(filename,"r");
if(fp==NULL){
printf("Cannot open the file,strike any key to exit!\n");
getchar();
exit(0);
}
for (int i = 0;!feof(fp);i++){
fscanf(fp,"%hhd",&x[i]);
}
N=x[0];
change(N);
int* result;
result = (int *)malloc(sizeof(int) * global_max);
int Dis[N][N], City[N];
for(int i=1;i<N;i++){
size=size*i;
}
char y[size];
for (int i=1;i<size+1;i++){
y[i] = x[i];
//printf("%d\n",y[i]);
}
for(int i=2; i < N + 1; i++){
for(int j=1; j < i ; j++){
Dis[j][i] = y[count];
Dis[i][j] = y[count];
count+=1;
//printf("(%d,%d),(%d,%d)",j,i,i,j);
//printf("%d\n",Dis[j][i]);
}
}
for(int i=0;i<N;i++){
City[i]=i + 1;//create the number of city with 1 ...... N
}
int curr_constraint = 0;
int v[N+1];
for (int i = 1; i < N+1; i++){
v[i] = 0;
}
for(int i = 1;i<N+1;i++){
curr_constraint += Dis[i][i+1];
}
v[1]= 1;
int sum = INT_MAX;
//printf("orginal ans is %d\n",ans);
//printf("Dis map:\n");
for( int i= 1;i<N+1;i++){
for(int j =1;j<N+1;j++){
if(i==j){
Dis[i][j]=0;
}
//printf("%d ",Dis[i][j]);
}
//printf("\n");
}
//printf("The orginal constraint is %d\n",curr_constraint);
int temp[N];
int* city_divided;
int cityNumber;
int current_ans;
SeqStack s;
if(nthreads > 1){
int remain = N % (nthreads - 1);
//int group_n = N /(nthreads - 1);
if(remain !=0){
if(my_rank <= remain && my_rank != 0){
cityNumber = ((N - remain)/(nthreads - 1)) + 1;
city_divided = (int*)malloc(cityNumber*sizeof(int));
for (int i = 0; i <cityNumber; i++)
{
city_divided[i] = City[(my_rank-1)*cityNumber + 1];
}
}else{
cityNumber = ((N - remain) / (nthreads - 1));
city_divided = (int*)malloc(cityNumber*sizeof(int));
for (int i = 0; i <cityNumber; i++)
{
city_divided[i] = City[(my_rank-1)*cityNumber + 1];
}
}
}else{
cityNumber = N / (nthreads - 1);
city_divided = (int*)malloc(cityNumber*sizeof(int));
for (int i = 0; i <cityNumber; i++)
{
city_divided[i] = City[(my_rank-1)*cityNumber + 1];
}
}
if(my_rank==0){
MPI_Recv(&ans, 1, MPI_INT, 0, 0, MPI_COMM_WORLD, MPI_STATUS_IGNORE);
for(int i=0;i<N;i++){
if(i != N-1){
printf("%d,",*(result+i));
}
else{
printf("%d",*(result+i));
}
}
printf("\n");
printf("Distance: %d\n",ans);
}
if(my_rank!=0){
for (int i = 0 ; i<cityNumber;i++){
current_ans = ans;
while(s.isEmpty(s)){
MPI_Recv(&ans, 1, MPI_INT, 0, 0, MPI_COMM_WORLD, MPI_STATUS_IGNORE);
result = tsp(Dis,v,N,1,city_divided[i],0,ans,result,temp,log);
s.Pop(&s,ans);
}
result = tsp(Dis,v,N,1,city_divided[i],0,ans,result,temp,log);
if(current_ans - ans > 0){
s.Push(ans);
MPI_Bcast(&ans,1,MPI_INT,0,MPI_COMM_WORLD);
}
}
}
}
else{
result = tsp(Dis,v,N,1,1,0,sum,result,temp,log);
}
for(int i=0;i<N;i++){
if(i != N-1){
printf("%d,",*(result+i));
}
else{
printf("%d",*(result+i));
}
}
printf("\n");
printf("Distance: %d\n",ans);
return 0;
}
I am trying to solve a special travelling salesman problem with mpi and c. I want make the master processor print the final information including the route and the shorest distance. the other processors with all city group run the tsp function, and when it has the shorter distance, use mpi_send or mpi_Bcast to other processors.Follow this logic, I meet a problem when I run the program.
enter image description here

Unreachable Node in Dijkstra's Algorithm

So I'm having trouble with Dijkstra's algorithm (src to dest). I looked at other answers and could not find the solution to my problem. I have used an adjacency list, thus I have a list for vertices, and each vertex has it's own edge list. My problem arises when I have a node that is unreachable. Specifically, it never gets visited thus I'm stuck in my allNotComp while loop. Can anyone help me with a solution? Code is below.
#include <stdlib.h>
#include <stdio.h>
int INFINITY = 9999;
struct edge
{
int vertexIndex;
int vertexWeight;
struct edge *edgePtr;
} edge;
struct vertex
{
int vertexKey;
struct edge *edgePtr;
struct vertex *vertexPtr;
}vertex;
struct vertex *Start = NULL;
void insertEdge(int vertex, int vertex2, int vertexWeight);
void insertVertex(int vertexKey);
int allNotComp(int comp[], int size);
void printPath(int prev[], int src, int dest, int size);
void dijkstra(int src, int size, int dest);
int cost(int curr, int i);
int main(int argc, char * argv[]) {
int k = 1;
int numVertices = atoi(argv[2]);
char* source = argv[3];
char* destination = argv[4];
int src = atoi(argv[3]);
int dest = atoi(argv[4]);
Start = &vertex;
Start->vertexKey = 0;
Start->vertexPtr = NULL;
Start->edgePtr = NULL;
int m = 0;
int flag = 0;
int flag2 = 0;
for(m = 0; m < numVertices; m++){
if(src == m) {
flag = 1;
}
if(dest == m) {
flag2 = 1;
}
}
if(!(flag && flag2)) {
printf("%s ", "ERROR: Src and/or Dest not valid.\n");
exit(0);
}
while(k < numVertices) {
insertVertex(k);
k++;
}
FILE *f = fopen(argv[1], "r");
int numbers[numVertices][numVertices];
char ch;
int i = 0;
int j = 0;
for(m = 0; m < numVertices*numVertices; m++) {
fscanf(f, "%d", &(numbers[i][j]));
j=j+1;
if(j == numVertices) {
i=i+1;
j=0;
}
}
for(i=0;i<numVertices;i++) {
for(j=0;j<numVertices;j++) {
if(i == j && numbers[i][j] != 0) {
printf("%s", "ERROR: All diagonals must be zero.\n");
exit(0);
}
if(i != j) {
insertEdge(i, j, numbers[i][j]);
}
}
}
dijkstra(src, numVertices, dest);
}
void insertEdge(int vertex, int vertex2, int vertexWeight)
{
if(vertexWeight == -1) return;
struct vertex *traverse;
if(vertex == Start->vertexKey) {
traverse = Start;
}
else {
while(traverse->vertexKey != vertex) {
traverse = traverse->vertexPtr;
}
}
struct edge *e,*e1,*e2;
e=traverse->edgePtr;
while(e&& e->edgePtr)
{
e=e->edgePtr;
}
e1=(struct edge *)malloc(sizeof(*e1));
e1->vertexIndex=vertex2;
e1->vertexWeight = vertexWeight;
e1->edgePtr=NULL;
if(e)
e->edgePtr=e1;
else
traverse->edgePtr=e1;
}
void insertVertex(int vertexKey) {
struct vertex *v, *v1, *v2;
v = Start->vertexPtr;
while(v && v->vertexPtr) {
v=v->vertexPtr;
}
v1=(struct vertex *)malloc(sizeof(*v1));
v1->vertexKey = vertexKey;
v1->vertexPtr = NULL;
v1->edgePtr = NULL;
if(v) {
v->vertexPtr = v1;
}
else {
Start->vertexPtr = v1;
}
}
void dijkstra(int src, int size, int dest) {
int comp[size];
int dist[size];
int prev[size];
int i;
for(i = 0; i<size; i++) {
comp[i] = 0;
dist[i] = INFINITY;
prev[i] = -1;
}
comp[src] = 1;
dist[src] = 0;
prev[src] = src;
int curr = src;
int k;
int minDist;
int newDist;
while(allNotComp(comp, size)) {
minDist = INFINITY;
for(i = 0; i<size;i++) {
if(comp[i] == 0) {
newDist = dist[curr] + cost(curr, i);
if(newDist < dist[i]) {
dist[i] = newDist;
prev[i] = curr; }
if(dist[i] < minDist) {
minDist = dist[i];
k=i; }
}
}
curr = k;
comp[curr] = 1;
}
if(dist[dest] < INFINITY) {
printPath(prev, src, dest, size);
printf(":%d\n", dist[dest]);
} else {
printf("%s\n", "NO PATH EXISTS BETWEEN THE TWO VERTICES!");
}
}
int allNotComp(int comp[], int size) {
int i;
for(i = 0; i < size; i++) {
if(comp[i] == 0) {
return 1;
}
}
return 0;
}
int cost(int curr, int i) {
struct vertex *travel;
struct edge *traverse;
travel = Start;
while(travel->vertexPtr != NULL) {
if(travel->vertexKey != curr) {
travel = travel->vertexPtr;
}
else{
break;
}
}
traverse = travel->edgePtr;
while(traverse->edgePtr != NULL) {
if(traverse->vertexIndex != i) {
traverse = traverse->edgePtr;
}
else{
break;
}
}
if(traverse->vertexIndex != i) {
return INFINITY;
}
return traverse->vertexWeight;
}
void printPath(int prev[], int src, int dest, int size) {
if(src == dest) {
printf("%d", src);
}
else {
printPath(prev, src, prev[dest], size);
printf("-%d", dest);
}
}
Although an unreachable node never gets visited, this situation can be detected. If the dists of all unvisited nodes are INFINITY, this means all remaining nodes are unreachable, and you should end the loop.

storing CSV file to Float Matrix in C

Code does not store the value after the last comma of the line into matrix...
full list.csv is like:
123456,57,45,,67,,56,,63,,,72,67,,,,34,56,,,,,56,,,,,,,,,,,,,,45,,,,,1523521
123457,57,45,,67,,56,,634,,,72,67,,,,34,56,,,,,56,,,,,,,,,,,,,,45,,,1234,,
123458,57,45,,67,,56,,63,,,724,67,,,,34,56,,,,,56,,,,,,,,,,,,,,45,,,,1234,
123459,57,45,,67,,56,,63,,,72,647,,,,34,56,,,,,56,,,,,,,,,,,,,,45,,,,,1234
123450,57,45,,67,,56,,63,,,72,67,,,,344,56,,,,,56,,,,,,,,,,,,,,45,,,,,124
123451,57,45,,67,,56,,63,,,72,67,,,,34,564,,,,,56,,,,,,,,,,,,,,45,,,,,
123452,57,45,,67,,56,,63,,,72,67,,,,34,56,,,,,564,,,,,,,,,,,,,,45,,,,,124
123453,57,45,,67,,56,,63,,,72,67,,,,34,56,,,,,56,,,,,,,,,,,,,,454,,,,,
123454,57,45,,67,,56,,63,,,72,67,,,,34,56,,,,,56,,,,,,,,,,,,,,45,,,,,124
123455,574,45,,67,,56,,63,,,72,67,,,,34,56,,,,,56,,,,,,,,,,,,,,45,,,,,
123465,57,454,,67,,56,,63,,,72,67,,,,34,56,,,,,56,,,,,,,,,,,,,,45,,,,,
123466,57,45,,674,,56,,63,,,72,67,,,,34,56,,,,,56,,,,,,,,,,,,,,45,,,,,124
This is my code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main(void)
{
int lines_allocated = 1000;
int max_line_len = 150;
double c[42][1000];
char **words = (char **)malloc(sizeof(char*)*lines_allocated);
if (words==NULL)
{
fprintf(stderr,"Out of memory (1).\n");
exit(1);
}
FILE *fp = fopen("full list.csv", "r");
if (fp == NULL)
{
fprintf(stderr,"Error opening file.\n");
exit(2);
}
int i;
for (i=0;1;i++)
{
int j;
if (i >= lines_allocated)
{
int new_size;
new_size = lines_allocated*2;
words = (char **)realloc(words,sizeof(char*)*new_size);
if (words==NULL)
{
fprintf(stderr,"Out of memory.\n");
exit(3);
}
lines_allocated = new_size;
}
words[i] = (char*)malloc(max_line_len);
if (words[i]==NULL)
{
fprintf(stderr,"Out of memory (3).\n");
exit(4);
}
if (fgets(words[i],max_line_len-1,fp)==NULL)
break;
for (j=strlen(words[i])-1;j>=0 && (words[i][j]=='\n' || words[i][j]=='\r');j--)
words[i][j]='\0';
}
int j;
int k=i;
for(j = 0; j < k; j++)
{
printf("%s\n", words[j]);
char *pptr = words[j];
int l;
for (l = 0; l < 42; l++)
{
char *ptr = strchr(pptr, ',');
if (ptr)
{
*ptr = 0;
c[l][j] = atof(pptr);
pptr = ptr + 1;
}
}
}
int l;
for (j = 0; j < k; j++)
{
printf("\n");
for (l = 0; l < 42; l++)
{
printf("%.2f\t", c[l][j]);
}
}
for (;i>=0;i--)
free(words[i]);
free(words);
return 0;
}
I think you miss a simple case: should be
#include <ctype.h>
...
char *ptr = strchr(pptr, ',');
if (ptr)
{
*ptr = 0;
c[l][j] = atof(pptr);
pptr = ptr + 1;
}
else if (isdigit(*pptr)) {
c[l][j] = atof(pptr);
}

Pointers and Dynamic Memory

I have a function that returns a pointer to an array. I'm running it in a loop and free() seems to be giving me problems. I'm not sure where, but it appears that somewhere in the main loop the memory that I'm trying to free is being used. I'm using Xcode 3.2.1 in 10.6 | Debug | x86_64 build.
The program will run through the main loop one time; the second time it encounters the free() it gives me the following error:
malloc: *** error for object 0x100100180: incorrect checksum for freed object -
object was probably modified after being freed.
Can someone point out (no pun intended) what I'm doing wrong with pointers here?
Here is the program:
int main(int argc, char **argv) {
int *partition;
int lowerLimit;
int upperLimit;
// snip ... got lowerLimit and upperLimit from console arguments
// this is the 'main loop':
for (int i = lowerLimit; i <= upperLimit; i += 2) {
partition = goldbachPartition(i);
printOutput(partition[0], partition[1], i);
free(partition); // I get problems on the second iteration here
}
return 0;
}
int *goldbachPartition(int x) {
int solved = 0;
int y, z;
int *primes;
int *result;
result = intAlloc(2);
primes = atkinsPrimes(x);
for (int i = intCount(primes)-1; i >= 0; i--) {
y = primes[i];
for (int j = 0; j < y; j++) {
z = primes[j];
if (z + y >= x) {
break;
}
}
if (z + y == x) {
solved = 1;
result[0] = y;
result[1] = z;
break;
} else if (y == z) {
result[0] = 0;
result[1] = 0;
break;
}
}
free(primes);
return result;
}
int *atkinsPrimes(int limit) {
int *primes;
int *initialPrimes;
int *filtered;
int *results;
int counter = 0;
int sqrtLimit;
int xLimit;
int resultsSize;
primes = intAlloc(limit+1);
intFillArray(primes, limit+1, 0);
sqrtLimit = floor(sqrt(limit));
xLimit = floor(sqrt((limit+1) / 2));
// these loops are part of the Atkins Sieve implementation
for (int x = 1; x < xLimit; x++) {
int xx = x*x;
for (int y = 1; y < sqrtLimit; y++) {
int yy = y*y;
int n = 3*xx + yy;
if (n <= limit && n % 12 == 7) {
primes[n] = (primes[n] == 1) ? 0 : 1;
}
n += xx;
if (n <= limit && (n % 12 == 1 || n % 12 == 5)) {
primes[n] = (primes[n] == 1) ? 0 : 1;
}
if (x > y) {
n -= xx + 2*yy;
if (n <= limit && n % 12 == 11) {
primes[n] = (primes[n] == 1) ? 0 : 1;
}
}
}
}
for (int n = 5; n < limit; n++) {
if (primes[n] == 1) {
for (int k = n*n; k < limit; k += n*n) {
primes[k] = 0;
}
}
}
initialPrimes = intAlloc(2);
if (limit >= 2) {
initialPrimes[counter++] = 2;
}
if (limit >= 3) {
initialPrimes[counter++] = 3;
}
filtered = intFilterArrayKeys(primes, limit+1);
results = intMergeArrays(initialPrimes, filtered, counter, trueCount(primes, limit+1));
resultsSize = counter + trueCount(primes, limit+1);
free(primes);
free(initialPrimes);
free(filtered);
results[resultsSize] = 0;
return results;
}
int trueCount(int *subject, int arraySize) {
int count = 0;
for (int i = 0; i < arraySize; i++) {
if (subject[i] == 1) {
count++;
}
}
return count;
}
int intCount(int *subject) {
// warning: expects 0 terminated array.
int count = 0;
while (*subject++ != 0) {
count++;
}
return count;
}
void intFillArray(int *subject, int arraySize, int value) {
for (int i = 0; i < arraySize; i++) {
subject[i] = value;
}
}
int *intFilterArrayKeys(int *subject, int arraySize) {
int *filtered;
int count = 0;
filtered = intAlloc(trueCount(subject, arraySize));
for (int i = 0; i < arraySize; i++) {
if (subject[i] == 1) {
filtered[count++] = i;
}
}
return filtered;
}
int *intMergeArrays(int *subject1, int *subject2, int arraySize1, int arraySize2) {
int *merge;
int count = 0;
merge = intAlloc(arraySize1 + arraySize2);
for (int i = 0; i < arraySize1; i++) {
merge[count++] = subject1[i];
}
for (int i = 0; i < arraySize2; i++) {
merge[count++] = subject2[i];
}
return merge;
}
int *intAlloc(int amount) {
int *ptr;
ptr = (int *)malloc(amount * sizeof(int));
if (ptr == NULL) {
printf("Error: NULL pointer\n");
}
return ptr;
}
void printOutput(int num1, int num2, int rep) {
if (num1 == 0) {
printf("%d: No solution\n", rep);
exit(0);
} else {
printf("%d = %d + %d\n", rep, num1, num2);
}
}
Why is intAlloc not returning int* ?
int *intAlloc(int amount) {
int *ptr;
ptr = (int *)malloc(amount * sizeof(int));
if(ptr == NULL) {
printf("Error: NULL pointer\n");
exit(1);
}
return ptr; //like this
}
EDIT (after your update):
On atkinsPrimes() where is filtered being intAlloc()ed?
int *atkinsPrimes(int limit) {
int *primes;
int *initialPrimes;
int *filtered;
int *results;
int resultsSize;
primes = intAlloc(limit+1);
// ...
initialPrimes = intAlloc(2);
// ...
resultsSize = counter + trueCount(primes, limit+1);
free(primes);
free(initialPrimes);
free(filtered); // Where was it intAlloc()ed?
results[resultsSize] = 0; // make the array 0-terminated to make it easier to work with
return results;
}
EDIT (after your N-th update):
This is a compilable version of your code. It ran smooth on my machine, no crashes. Compiled with g++ (due to declarations of variables inside the for statement):
g++ (Debian 4.3.2-1.1) 4.3.2
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
int *goldbachPartition(int x);
int *atkinsPrimes(int limit);
int trueCount(int *subject, int arraySize);
int intCount(int *subject) ;
void intFillArray(int *subject, int arraySize, int value);
int *intFilterArrayKeys(int *subject, int arraySize);
int *intAlloc(int amount);
void printOutput(int num1, int num2, int rep) ;
int *intMergeArrays(int *subject1, int *subject2, int arraySize1, int arraySize2);
int main(int argc, char **argv) {
if (argc < 3) {
printf("Usage: ./program <lower> <upper>\n");
return 0;
}
int *partition;
int lowerLimit = atoi(argv[1]);
int upperLimit = atoi(argv[2]);
// snip ... got lowerLimit and upperLimit from console arguments
// this is the 'main loop':
for (int i = lowerLimit; i <= upperLimit; i += 2) {
partition = goldbachPartition(i);
printOutput(partition[0], partition[1], i);
free(partition); // I get problems on the second iteration here
}
return 0;
}
int *goldbachPartition(int x) {
int solved = 0;
int y, z;
int *primes;
int *result;
result = intAlloc(2);
primes = atkinsPrimes(x);
for (int i = intCount(primes)-1; i >= 0; i--) {
y = primes[i];
for (int j = 0; j < y; j++) {
z = primes[j];
if (z + y >= x) {
break;
}
}
if (z + y == x) {
solved = 1;
result[0] = y;
result[1] = z;
break;
} else if (y == z) {
result[0] = 0;
result[1] = 0;
break;
}
}
free(primes);
return result;
}
int *atkinsPrimes(int limit) {
int *primes;
int *initialPrimes;
int *filtered;
int *results;
int counter = 0;
int sqrtLimit;
int xLimit;
int resultsSize;
primes = intAlloc(limit+1);
intFillArray(primes, limit+1, 0);
sqrtLimit = floor(sqrt(limit));
xLimit = floor(sqrt((limit+1) / 2));
for (int x = 1; x < xLimit; x++) {
int xx = x*x;
for (int y = 1; y < sqrtLimit; y++) {
int yy = y*y;
int n = 3*xx + yy;
if (n <= limit && n % 12 == 7) {
primes[n] = (primes[n] == 1) ? 0 : 1;
}
n += xx;
if (n <= limit && (n % 12 == 1 || n % 12 == 5)) {
primes[n] = (primes[n] == 1) ? 0 : 1;
}
if (x > y) {
n -= xx + 2*yy;
if (n <= limit && n % 12 == 11) {
primes[n] = (primes[n] == 1) ? 0 : 1;
}
}
}
}
for (int n = 5; n < limit; n++) {
if (primes[n] == 1) {
for (int k = n*n; k < limit; k += n*n) {
primes[k] = 0;
}
}
}
initialPrimes = intAlloc(2);
if (limit >= 2) {
initialPrimes[counter++] = 2;
}
if (limit >= 3) {
initialPrimes[counter++] = 3;
}
filtered = intFilterArrayKeys(primes, limit+1);
results = intMergeArrays(initialPrimes, filtered, counter, trueCount(primes, limit+1));
resultsSize = counter + trueCount(primes, limit+1);
free(primes);
free(initialPrimes);
free(filtered);
results[resultsSize] = 0;
return results;
}
int trueCount(int *subject, int arraySize) {
int count = 0;
for (int i = 0; i < arraySize; i++) {
if (subject[i] == 1) {
count++;
}
}
return count;
}
int intCount(int *subject) {
// warning: expects 0 terminated array.
int count = 0;
while (*subject++ != 0) {
count++;
}
return count;
}
void intFillArray(int *subject, int arraySize, int value) {
for (int i = 0; i < arraySize; i++) {
subject[i] = value;
}
}
int *intFilterArrayKeys(int *subject, int arraySize) {
int *filtered;
int count = 0;
filtered = intAlloc(trueCount(subject, arraySize));
for (int i = 0; i < arraySize; i++) {
if (subject[i] == 1) {
filtered[count++] = i;
}
}
return filtered;
}
int *intMergeArrays(int *subject1, int *subject2, int arraySize1, int arraySize2) {
int *merge;
int count = 0;
merge = intAlloc(arraySize1 + arraySize2);
for (int i = 0; i < arraySize1; i++) {
merge[count++] = subject1[i];
}
for (int i = 0; i < arraySize2; i++) {
merge[count++] = subject2[i];
}
return merge;
}
int *intAlloc(int amount) {
int *ptr;
ptr = (int *)malloc(amount * sizeof(int));
if (ptr == NULL) {
printf("Error: NULL pointer\n");
}
return ptr;
}
void printOutput(int num1, int num2, int rep) {
if (num1 == 0) {
printf("%d: No solution\n", rep);
exit(0);
} else {
printf("%d = %d + %d\n", rep, num1, num2);
}
}
Since you are still omitting some source, I can only imagine that the problem is hidden there.
EDIT: (my last update)
To assist your debugging, you should replace your main() function by the one below:
int main(int argc, char **argv)
{
int *primes = NULL;
primes = atkinsPrimes(44); // Evil magic number
free(primes);
return 0;
}
Having a minimal example to reproduce the behavior you pointed out is much better then the whole thing. Have fun with atkinsPrimes(44)

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