pointers-memory · intermediate · ~15 min

Shrink with realloc

Shrink a buffer while keeping its prefix.

Challenge

Implement int *shrink(int *a, int oldn, int newn) that shrinks the heap array to newn elements (newn <= oldn) with realloc, preserving the first newn values, and returns the pointer.

Starter code

#include <stdlib.h>

int *shrink(int *a, int oldn, int newn) {
    /* TODO */
    return a;
}

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