#include <stdio.h>
 
void swap_pointer(int *pp[]);
 
int main(void)
{
    int a = 1;
    int b = 2;
 
    int *p[2] = {&a, &b};
 
    int size = sizeof(p) / sizeof(p[0]);
 
    for (int i = 0; i < size; i++) {
        printf("before: p[%d] : %p\n", i, p[i]);
    }
 
    swap_pointer(p);
 
    for (int i = 0; i < size; i++) {
        printf("after : p[%d] : %p\n", i, p[i]);
    }
 
    return 0;
}
 
void swap_pointer(int *pp[])
{
    int *temp;
 
    temp = pp[0];
    pp[0] = pp[1];
    pp[1] = temp;
}

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