#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <assert.h>

void swap(int* a_lhs, int* a_rhs) {
    int lhs = *a_lhs;  // lhs gets the "value at address a_lhs"
    int rhs = *a_rhs;  // rhs gets the "value at address a_rhs"

    *a_lhs = rhs;  // write the rhs at the address a_lhs.
    *a_rhs = lhs;  // write the lhs at the address a_rhs.
}

int main(int argc, char* argv[]) {
    int n1 = 3;
    int n2 = 4;
    printf("# n1 == %d    n2 == %d\n", n1, n2);
    printf("\n");

    swap(&n1, &n2);   // passing the address of n1 and address of n2 to swap(…)
    printf("swap(&n1, &n2);\n");

    printf("\n");
    printf("# n1 == %d    n2 == %d\n", n1, n2);
    //swap(…);
    return EXIT_SUCCESS;
}
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