Question

求C语言大神，期末考试唯一的一道题，希望能认真对待，测试完没问题马上采纳！谢谢！

Answer 1

这种题，就是练练打字而已。那就练练吧——

//#include "stdafx.h"//vc++6.0加上这一行.
#include "stdio.h"
int main(void){
    double a,b;
    int n;
    printf("|-----------------------------------------------|\n");
    printf("|                    calculator                 |\n");
    printf("|-----------------------------------------------|\n");
    printf("|                     1---add                   |\n");
    printf("|                     2---sub                   |\n");
    printf("|                     3---mul                   |\n");
    printf("|                     4---div                   |\n");
    printf("|                     0---quit                  |\n");
    printf("|-----------------------------------------------|\n");
    while(1){
        printf("Please choice(0-4):");
        if(scanf("%d",&n),n==1){
            printf("Please the first data:");
            scanf("%lf",&a);
            printf("Please the second data:");
            scanf("%lf",&b);
            printf("Result of calculator:\n%f + %f = %f\n",a,b,a+b);
        }
        else if(n==2){
            printf("Please the first data:");
            scanf("%lf",&a);
            printf("Please the second data:");
            scanf("%lf",&b);
            printf("Result of calculator:\n%f - %f = %f\n",a,b,a-b);
        }
        else if(n==3){
            printf("Please the first data:");
            scanf("%lf",&a);
            printf("Please the second data:");
            scanf("%lf",&b);
            printf("Result of calculator:\n%f x %f = %f\n",a,b,a*b);
        }
        else if(n==4){
            printf("Please the first data:");
            scanf("%lf",&a);
            while(1){
                printf("Please the second data:");
                if(scanf("%lf",&b),b) break;
                printf("Error,divisor cannot be 0,redo:");
            }
            printf("Result of calculator:\n%f ÷ %f = %f\n",a,b,a/b);
        }
        else if(n==0) break;
        printf("Continue(y/n)?\n");
        getchar();
        if((getchar()|0x20)=='n') break;
    }
    return 0;
}

Answer 2

#include <stdio.h>
#include <math.h>

void main()
{
	int id;
	double a, b, c;
	char d;
	printf("                |---------------------------------------------|\n");
	printf("                |               calculator                    |\n");
	printf("                |---------------------------------------------|\n");
	printf("                |                1---add                      |\n");
	printf("                |                2---sub                      |\n");
	printf("                |                3---mul                      |\n");
	printf("                |                4---div                      |\n");
	printf("                |                0---quit                     |\n");
	printf("                |---------------------------------------------|\n");
	while (1)
	{
		printf("                   please choice<0-4>:");
		scanf("%d", &id);
		if (id == 0)
			printf("quit\n");
		else
		{
			printf("                   please the first data:");
			scanf("%lf", &a);
			printf("                   please the second data:");
			scanf("%lf", &b);
			printf("                   result of calulator:\n");
			if (id == 4 && fabs(b) < 1e-6)
				printf("                   the second data is error(=0)\n");
			else
			{
				if (id == 1) c = a + b;
				else if (id == 2) c = a - b;
				else if (id == 3) c = a * b;
				else if (id == 4) c = a / b;
				printf("                   %lf - %lf = %lf\n", a, b, c);
			}
		}
		printf("                   continue (y/n)? ");
		fflush(stdin);
		scanf("%c", &d);
		fflush(stdin);
		if (d == 'n') break;
	}
}

追问

大神 这是什么情况？

追答

什么?每种情形下相应的运算符号改下

追问

悬赏已提高到120 希望大神能帮忙

我对这个是一窍不通……

追答

字太多 发不了 发到私信上了

追问

没有啊 大神

Answer 3

#include <stdio.h>
int main()
{
int choice = 0;
int firstNum;
int secondNum;
printf("[1] Add\n");
printf("[2] Subtract\n");
printf("[3] Multiply\n");
printf("[4] Divide\n");
printf("Enter your choice : ");
scanf("%d", &choice);
printf("first num: ");
scanf("%d", &firstNum);
printf("Second num: ");
scanf("%d", &secondNum);
switch(choice)
{
case 1: // Add
printf("%d + %d = %d\n",firstNum,secondNum, firstNum + secondNum);
break;
case 2:// Subtract
printf("%d - %d = %d\n",firstNum,secondNum, firstNum - secondNum); // Subtract
break;
case 3:
printf("%d - %d = %d\n",firstNum,secondNum, firstNum * secondNum);// Multiply
break;
case 4:
printf("%d - %d = %d\n",firstNum,secondNum, firstNum / secondNum); // Divide
break;
default:
printf("Enter Wrong!\n");
}
return 0;
}

追问