void main(){int a;scanf("%d", &a);switch (a){case 1:printf("可口可乐");break;case 2:printf("雪碧");break;case 3:printf("芬达");break;case 4:printf("百事可乐");break;case 5:printf("非常可乐");break;default:printf("输入错误，请重新输入");}
void main(){int data1, data2;char op;printf("请输入一个算式：");scanf("%d%c%d", &data1, &op, &data2);switch (op){case'+':printf("%d+%d=%d\n", data1, data2, data1 + data2);break;case'-':printf("%d-%d=%d\n", data1, data2, data1 - data2);break;case'*':printf("%d*%d=%d\n", data1, data2, data1 * data2);break;case'/':if (data2 == 0)printf("除数不能为0\n");elseprintf("%d/%d=%d\n", data1, data2, data1 / data2);break;default:printf("输入错误，请重新输入！\n");}}
case后字母加空格；
scanf输入字符有顺序限制
#include<stdio.h>int main() {int score;printf("请输入成绩分数\n");scanf_s("%d", &score);if (score < 0 || score>100) {printf("输入的成绩有误，请输入0-100区间的分数");}else {if (score >= 90 && score < 100) {printf("成绩等级为A\n");}else if (score >= 80 && score < 89) {printf("成绩等级为B\n");}else if (score >= 70 && score < 79) {printf("成绩等级为C\n");}else if (score >= 60 && score < 69) {printf("成绩等级为D\n");}else {printf("成绩等级为E\n");}}printf("成绩评定结束");return 0;}
void main(){int mouth, year;float price, money;printf("请输入月份：");scanf("%d", &mouth);printf("请输入年龄：");scanf("%d", &year);printf("请输入价格：");scanf("%f", &price);if (mouth < 5 && mouth>10){if (year < 14)money = price * 0.5;else if (year < 65)money = price * 0.8;elsemoney = 0;}else {if (year < 14)money = price*0.5;else if (year < 65)money = price ;elsemoney = 0;}printf("最终的价格是%f", money);}注意%d%f的格式
void main(){float z, height, weight;printf("请输入你的身高");scanf("%f", &height);printf("请输入你的体重：");scanf("%f", &weight);z = weight / height / height;printf("您的体重指数是：%f", z);if (z < 18)printf("偏瘦");else if (z < 25)printf("标准");else if (z < 30)printf("微胖");else if (z < 40)printf("肥胖");elseprintf("很胖");}
