Binary tree not adding strings from file - c

Question

#include <stdio.h>
#include <stdlib.h>
struct treeNode
{
char *word;
int NumberCnt;
struct treeNode *rightPTR, *leftPTR;
};
typedef struct treeNode node;
node *rootPTR = NULL;
void freeTree(node *currPTR)
{
if (currPTR!= NULL)
{
freeTree(currPTR -> leftPTR);
free(currPTR);
freeTree(currPTR -> rightPTR);
}
}
void printTree(node *currPTR)
{
if (currPTR != NULL)
{
printTree(currPTR ->leftPTR);
printf("%s appeared:%d times\n", currPTR->word, currPTR->NumberCnt);
printTree(currPTR ->rightPTR);
}
}
int insertNode (char* input)
{
node *tempPTR = malloc(sizeof(node));
tempPTR -> word = input;
tempPTR -> NumberCnt=0;
tempPTR -> leftPTR = NULL;
tempPTR -> rightPTR = NULL;
if (rootPTR == NULL)
{
rootPTR = tempPTR;
rootPTR -> NumberCnt++;
}
else
{
node *currPTR = rootPTR;
node *prevPTR = NULL;
while (currPTR != NULL)
{
int comp = strcmp(input, (currPTR->word));
if (comp == 0)
{
printf ("Entry already exists\n");
currPTR->NumberCnt++;
return 1;
}
else if (comp < 0)
{
prevPTR = currPTR;
currPTR = currPTR->leftPTR;
}
else if (comp > 0)
{
prevPTR = currPTR;
currPTR = currPTR->rightPTR;
}
}
int comp = strcmp(input, (prevPTR ->word));
if (comp < 0)
{
prevPTR->leftPTR = tempPTR;
prevPTR ->NumberCnt++;
}
else if (comp > 0)
{
prevPTR->rightPTR = tempPTR;
prevPTR->NumberCnt++;
}
return 0;
}
printf("root1%s\n",rootPTR->word);
return 2;
}
int search(char* input)
{
if (input == rootPTR ->word)
{
printf("Node found %s\n", rootPTR->word);
return 0;
}
else
{
if (input < rootPTR ->word)
{
node *currPTR = rootPTR->leftPTR;
while (currPTR != NULL)
{
if (input == currPTR->word)
{
printf("Node found %s\n", currPTR->word);
return 0;
}
else if (input < currPTR->word)
{
currPTR = (currPTR -> leftPTR);
}
else if (input > currPTR->word)
{
currPTR = (currPTR -> rightPTR);
}
}
printf ("Node not in tree\n");
return 1;
}
if (input > rootPTR ->word)
{
node *currPTR = rootPTR->rightPTR;
while (currPTR != NULL)
{
if (input == currPTR->word)
{
printf ("Node found %s\n", currPTR->word);
return 0;
}
else if (input < currPTR->word)
{
currPTR = (currPTR -> leftPTR);
}
else if (input > currPTR->word)
{
currPTR = (currPTR ->rightPTR);
}
}
printf ("Node not in tree\n");
return 1;
}
}
return 2;
}
void fixWord(char* buff)
{
char* unfixed = buff;
char* fixed = buff;
while (*unfixed)
{
if (isalpha(*unfixed))
{
*fixed=tolower(*unfixed);
*fixed++;
}
*unfixed++;
}
*fixed=0;
}
int main()
{
FILE *ptr_file;
char buff [100];
//ptr_file = fopen ("sherlock.txt", "r");
ptr_file = fopen ("input.txt", "r");
if (!ptr_file)
printf("File read error");
while(fscanf(ptr_file, "%s ", buff ) != EOF)
{
int comparison = strcmp(buff, "endoffile");
if (comparison == 0)
{
return 0;
}
fixWord(buff);
insertNode(buff);
}
fclose(ptr_file);
printf("root:%s\n", rootPTR->word);
return 0;
}
Ok I have this binary tree which is taking string inputs from a file. It works if I pass strings directly to the tree, however when I attempt to pass it the strings I read in form the file it keeps on replacing the root node and does not add them correctly to the tree.

Answer 1

buff is current line value and overwritten on each line reading:
insertNode(buff);
insertNode assigns overwriten buffer.
int insertNode (char* input)
{
node *tempPTR = malloc(sizeof(node));
tempPTR -> word = input;
....
So, you should dynamic allocation for input value as:
int insertNode (char* input)
{
node *tempPTR = malloc(sizeof(node));
tempPTR -> word = strdup(input);
....

Answer 2

You're passing buff to your insert function, and it's storing that in the node. So all your nodes will end up pointing to the same address, that of buff in main.
You need to allocate storage for each string in each node, and copy your input into that. And remember to deallocate properly when you delete your tree.
strdup can be handy for that if your library has it.