I just cant figure out where i did wrong in my maxheap implementation... i didnt even discover it had a problem until i changed it to a minheap to use in a disjktra

i'm pretty sure it's related to the fact that arrays in C start at 0, but i cant seem to find the error... so i tought an outsider eye couldnt pinpoint it since i probably keep making the same error over and over again

here's the code

i apreciated all your help

*Edited code to hv a main and it now shows my problem*

Code:#include <stdio.h> #include <stdlib.h> #define LEFT(x) (2*x) /* left child of a node */ #define RIGHT(x) ((2*x)+1) /* right child of a node */ #define PARENT(x) (x/2) /* parent of a node */ #define SWAP(tmp,x,y) tmp = x ; x = y ; y = tmp /* swap to variables */ void max_heapify(int A[], int i, int size) { int l, r, largest, temp; l = LEFT(i); r = RIGHT(i); if(l <= size && A[l-1] > A[i-1]) largest = l; else largest = i; if(r <= size && A[r-1] > A[largest-1]) largest = r; if(largest != i) { SWAP(temp, A[i-1], A[largest-1]); max_heapify(A, largest, size); } } void build_max_heap(int A[], int size) { int i; for(i = (size/2); i>0; i--) max_heapify(A, i, size); } int heap_maximum(int A[]) { return A[0]; } int heap_extract_max(int A[], int *size) { int max; if(*size < 1) { printf("Heap underflow.\n"); return -1; } max = A[0]; A[0] = A[(*size)-1]; *size = (*size)-1; max_heapify(A, 1, *size); return max; } void heap_increase_key(int A[], int i, int key) { int temp; if(key<A[i]) { printf("New key is smaller than current key.\n"); return; } A[i] = key; while(i > 0 && A[PARENT(i)] < A[i]) { SWAP(temp, A[i], A[PARENT(i)]); i = PARENT(i); } } void max_heap_insert(int A[], int *size, int max_size, int key) { if(*size >= max_size) { printf("Heap capacity exceeded, new element not added.\n"); return; } *size = (*size)+1; A[*size]=-1; /*should be - infinity*/ heap_increase_key(A, *size, key); } int main(int argc, char *argv[]) { int maxsize, size, i; int *array; maxsize=size=5; i=0; array = malloc(maxsize*sizeof(int)); while(i<maxsize) { array[i]=-1; i++; } array[0]=0; array[4]=7; array[3]=3; build_max_heap(array, size); for(i=0; i< size; i++) printf("%i ", array[i]); printf("\n"); heap_extract_max(array, &size); for(i=0; i< size; i++) printf("%i ", array[i]); printf("\n"); max_heap_insert(array, &size, maxsize, 2); for(i=0; i< size; i++) printf("%i ", array[i]); printf("\n"); heap_extract_max(array, &size); for(i=0; i< size; i++) printf("%i ", array[i]); printf("\n"); max_heap_insert(array, &size, maxsize, 10); for(i=0; i< size; i++) printf("%i ", array[i]); printf("\n"); free(array); return 0; }