c13

输入两个数和运算符，输出结果

#include<stdio.h>
void main()
{
	double a, b, c;
	char ch;
	printf("输入两个数和一个字符\n");
	scanf("%lf,%lf,%c", &a, &b, &ch);
	switch (ch)
	{
	case'+':c = a + b;
		break;
	case'-':c = a - b;
		break;
	case'*':c = a * b;
		break;
	case'/':
	{
		if (b == 0)
			printf("error\n");
		else
			c = a / b;
	}
	default:printf("error\n");
	}
	printf("%.2lf %c %.2lf = %.2lf\n", a, ch, b, c);
}