/* 例2. 2整数の和と差を計算して返す関数(サブルーチン) */

#include <stdio.h>

/* 関数プロトタイプ宣言 */
int watosa(int x1, int x2, int *wa, int *sa);

main()
{
    int a, b;
    int sum, diff; 

    a = 10 ;
    b = 8  ; 
    printf("a = %d b = %d\n", a, b);
    watosa(a, b, &sum, &diff);
    printf("wa = %d sa = %d\n", sum, diff);

  watosa(25, 30, &sum, &diff);
  printf("wa = %d sa = %d\n", sum, diff);
}

int watosa(int x1, int x2, int *wa, int *sa)
{
    *wa = x1 + x2;
    *sa = x1 - x2;
    return;
}