Logic check not outputting as expected. (Sudoku checker) C - c

Question

I have a function that checks all the rows of a sudoku board and outputs and exits if invalid.
(a valid row has 1-9 on a 9 square row)
I've been staring at my logic for 30 minutes and can't see why a board that I know is valid keeps spitting out invalid.
To try and make it a little easier to read, here's the part in question...
void* checkRow(void* p){
int check[9] = {0};
parameters* temp = (parameters*) p;
int tempRow = temp -> row;
int tempCol = temp -> col;
for (int i = 0; i < SIZE; i++){ // looping to find each # 1-9
for (int j = 0; j < SIZE; j++){
if (board[i][j] == 1)
check[0] = 1;
if (board[i][j] == 2)
check[1] = 1;
if (board[i][j] == 3)
check[2] = 1;
if (board[i][j] == 4)
check[3] = 1;
if (board[i][j] == 5)
check[4] = 1;
if (board[i][j] == 6)
check[5] = 1;
if (board[i][j] == 7)
check[6] = 1;
if (board[i][j] == 8)
check[7] = 1;
if (board[i][j] == 9) // changing value to 1 if found
check[8] = 1;
int k = 0;
while(k < 9){
if (check[k] == 0){
printf("invalid solution"); // should only print if 1-9 isn't found right?
exit(0);
}
k++;
}
memset(check, 0, sizeof(check)); // resetting array to zero
}
}
}
Here's everything, just in case.
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <pthread.h>
#define SIZE 9
typedef struct{ // referenced from assignment page
int row;
int col;
} parameters;
int board[SIZE][SIZE]; // global variable holding board
pthread_t tRow, tCol, t1, t2, t3, t4, t5, t6, t7, t8, t9;
void setThreads();
void* checkRow(void* p);
int main(int argc, char **argv){ // referenced project 1. Supplies command line input for file
FILE *fp;
fp = fopen(argv[1], "r");
if (fp == NULL) // validity check
exit(1);
for (int i = 0; i < SIZE; i++){
for(int j = 0; j < SIZE; j++){
fscanf(fp, "%d", &board[i][j]);
}
}
setThreads();
printf("rows check out");
return 0;
}
void setThreads(){
parameters *rowcolparameter = (parameters *) malloc(sizeof(parameters));
rowcolparameter -> row = 0;
rowcolparameter -> col = 0;
parameters *square1 = (parameters *) malloc(sizeof(parameters));
square1 -> row = 0;
square1 -> col = 0;
parameters *square2 = (parameters *) malloc(sizeof(parameters));
square2 -> row = 0;
square2 -> col = 3;
parameters *square3 = (parameters *) malloc(sizeof(parameters));
square3 -> row = 0;
square3 -> col = 6;
parameters *square4 = (parameters *) malloc(sizeof(parameters));
square4 -> row = 3;
square4 -> col = 0;
parameters *square5 = (parameters *) malloc(sizeof(parameters));
square5 -> row = 3;
square5 -> col = 3;
parameters *square6 = (parameters *) malloc(sizeof(parameters));
square6 -> row = 3;
square6 -> col = 6;
parameters *square7 = (parameters *) malloc(sizeof(parameters));
square7 -> row = 6;
square7 -> col = 0;
parameters *square8 = (parameters *) malloc(sizeof(parameters));
square8 -> row = 6;
square8 -> col = 3;
parameters *square9 = (parameters *) malloc(sizeof(parameters));
square9 -> row = 6;
square9 -> col = 6;
pthread_create(&tRow, NULL, checkRow, rowcolparameter);
pthread_join(tRow, NULL);
}
void* checkRow(void* p){
int check[9] = {0};
parameters* temp = (parameters*) p;
int tempRow = temp -> row;
int tempCol = temp -> col;
for (int i = 0; i < SIZE; i++){ // looping to find each # 1-9
for (int j = 0; j < SIZE; j++){
if (board[i][j] == 1)
check[0] = 1;
if (board[i][j] == 2)
check[1] = 1;
if (board[i][j] == 3)
check[2] = 1;
if (board[i][j] == 4)
check[3] = 1;
if (board[i][j] == 5)
check[4] = 1;
if (board[i][j] == 6)
check[5] = 1;
if (board[i][j] == 7)
check[6] = 1;
if (board[i][j] == 8)
check[7] = 1;
if (board[i][j] == 9)
check[8] = 1;
int k = 0;
while(k < 9){
if (check[k] == 0){
printf("invalid solution"); // it should only say invalid if 1-9 wasn't found right?
exit(0);
}
k++;
}
memset(check, 0, sizeof(check)); // resetting array to 0
}
}
}
Thank you.

Answer 1

It seems that the "check part" is inside the inner loop! Shouldn't it be outside the inner loop. Like:
for (int i = 0; i < SIZE; i++){ // looping to find each # 1-9
for (int j = 0; j < SIZE; j++){
if (board[i][j] == 1)
check[0] = 1;
if (board[i][j] == 2)
check[1] = 1;
if (board[i][j] == 3)
check[2] = 1;
if (board[i][j] == 4)
check[3] = 1;
if (board[i][j] == 5)
check[4] = 1;
if (board[i][j] == 6)
check[5] = 1;
if (board[i][j] == 7)
check[6] = 1;
if (board[i][j] == 8)
check[7] = 1;
if (board[i][j] == 9) // changing value to 1 if found
check[8] = 1;
} // End the inner loop
// Now do the check
int k = 0;
while(k < 9){
if (check[k] == 0){
printf("invalid solution"); // should only print if 1-9 isn't found right?
exit(0);
}
k++;
}
memset(check, 0, sizeof(check)); // resetting array to zero
}
BTW: you can reduce the inner-loop code a lot like this:
// inner loop
for (int j = 0; j < SIZE; j++){
if (board[i][j] < 1 || board[i][j] > 9) exit(1); // Illegal board value
check[board[i][j] - 1] = 1; // Mark value as found
}