Hi, guys, i need some help, as i can't find a mistake in my code for some hours.
I'm expiriencing a problem in function makeCodes, which should make huffman codes for my symbols. In my head this works just fine, recursively making codes, but my Visual Studio crashes on the first strcpy. What's wrong? Maybe i have no permission to copy strings, or anything?
P.S. Sorry for my english :(
#include<stdio.h>
#include<stdlib.h>
#include <string.h>
#define SIZE 256
struct SYM
{
unsigned char ch; //ascii
float freq; //symbol frequency
char code[SIZE]; //new huffman code
SYM *left; //left hand of tree
SYM *right; //right hand of tree
};
SYM* huffTree(SYM *syms[], int N) //array of SYM structs and size N
{
SYM *temp=(SYM*)malloc(sizeof(SYM));
temp->freq=syms[N-1]->freq+syms[N-2]->freq;
temp->code[0]=0;
temp->left=0;
temp->right=0;
temp->left=syms[N-2];
temp->right=syms[N-1];
if(N==2)
return temp;
else
{
for(int i=0;i<N;i++)
{
if(temp->freq>syms[i]->freq)
{
syms[N-1]=syms[i];
syms[i]=temp;
temp=syms[N-1];
}
}
return huffTree(syms, N-1);
}
}
void makeCodes(SYM *root)
{
if (root->left)
{
strcpy(root->left->code,root->code);
strcat(root->left->code,"0");
makeCodes(root->left);
}
if (root->right)
{
strcpy(root->right->code,root->code);
strcat(root->right->code,"1");
makeCodes(root->right);
}
}
int main()
{
int i=5;
SYM *syms[SIZE];
SYM arr[SIZE];
arr[0].ch='a';
arr[0].freq=0.4;
arr[1].ch='b';
arr[1].freq=0.3;
arr[2].ch='c';
arr[2].freq=0.1;
arr[3].ch='d';
arr[3].freq=0.1;
arr[4].ch='e';
arr[4].freq=0.1;
syms[0]=&arr[0];
syms[1]=&arr[1];
syms[2]=&arr[2];
syms[3]=&arr[3];
syms[4]=&arr[4];
SYM* root=huffTree(syms, i);
makeCodes(root);
}
