#include <stdio.h>

int sum(int x, int y);
int diff(int x, int y);

void main()
{
	int num1 = 10;
	int num2 = 15;
	
	printf("２つの整数の和：%d\n", sum(num1, num2));
	printf("２つの整数の差：%d\n", diff(num1, num2));
}

/* 加算関数 */
int sum(int x, int y)
{
	return x + y;
}

/* 減算関数 */
int diff(int x, int y)
{
	return x - y;
}