switch四则运算： + - * /
#include<stdio.h>#include<stdlib.h>int main (){ int h =1;while(h!=-1){int a,b;char op;printf("please enter the expression");scanf("%d%c%d",&a,&op,&b);switch (op){case + :printf("%d+%d=%d\n",a,b,a+b);break;case - :printf("%d-%d=%d\n",a,b,a-b);break;case * :printf("%d*%d=%d\n",a,b,a*b);break;case /:printf("%d/%d=%d\n",a,b,a/b);break;default :printf("Invalid opreator!\n");}}return 0;}
五个产品：记录每个产品的销售数量和总的销售额
#include<stdio.h>#include<stdlib.h>int main (){int a=0;int b=0;int c=0;int d=0;int e=0;int i;printf("请输入产品号：\n");scanf_s("%d",&i);while(i!=-1)
