＋－×÷四则运算 switch.cpp

来自「我正在学习C编程」· C++ 代码 · 共 25 行

#include<stdio.h>   /**/
void main()
{
	char c;
	float x,y;
	printf("\n\t四则运算,输入两个数(任意一数为0时结束)和＋－×÷运算符,求值\n\n");
	while(1)
	{
		printf("  输入欲计算的两个数: \n");
		printf("  Number1: "); 	scanf("%f",&x);if(x==0)break;   //输入非数值时出错?
		printf("  Number2: "); 	scanf("%f",&y);if(y==0)break;
		if(getchar()=='\n');      //不完整,连续输入两个以上数字时出错?
		printf("  输入四则运算符: "); 	scanf("%c",&c);
		switch(c)
			{case '+':printf("  %f＋%f=%f\n",x,y,x+y);break;
			 case '-':printf("  %f－%f=%f\n",x,y,x-y);break;
			 case '*':printf("  %f×%f=%f\n",x,y,x*y);break;
			 case '/':printf("  %f÷%f=%f\n",x,y,x/y);break;
			 default:printf("  Input error四则运算符输入错误!\n");
			}
		if(getchar()=='\n'){;}
		printf("\n");
	}
}