// 24T3 COMP1511 Week 5 Lecture 2
// variables/data are passed into functions by value
// a copy of the value gets passed into the function
// so changes made in the function are on the local copy

#include <stdio.h>

void update(int x, int y);
void swap(int x, int y);

int main(void) {
    int x = 2;
    int y = 5;

    printf("%d %d\n", x, y);
    
    update(x,y);
    printf("%d %d\n", x, y);
    
    swap(x, y);
    printf("%d %d\n", x, y);
    return 0;
}

// This function will only modify the local copy of x and y
void update(int x, int y) {
    x = x + 1;
    y = y - 1;
}

// This function will only modify the local copy of x and y
void swap(int x, int y) {
    int tmp = x;
    x = y;
    y = tmp;
}