56. 구조체의 값 전달과 포인터 전달

1#include <stdio.h>
2 
3struct Point {
4    int x;
5    int y;
6};
7 
8void moveVal(struct Point p, int d) {
9    p.x += d;
10    p.y += d;
11}
12 
13void movePtr(struct Point *p, int d) {
14    p->x += d;
15    p->y -= d;
16}
17 
18struct Point mirror(struct Point p) {
19    int t = p.x;
20    p.x = p.y;
21    p.y = t;
22    return p;
23}
24 
25int main() {
26    struct Point a = {3, 8};
27    struct Point b = a;
28    moveVal(a, 5);
29    movePtr(&b, 2);
30    printf("%d %d / %d %d\n", a.x, a.y, b.x, b.y);
31    struct Point arr[2] = {a, b};
32    struct Point *q = arr;
33    for (int i = 0; i < 2; i++) {
34        movePtr(q + i, (i + 1) * 3);
35    }
36    a = mirror(arr[1]);
37    printf("%d %d / %d %d / %d\n", arr[0].x, arr[0].y, a.x, a.y, b.x);
38    return 0;
39}