C语言题目求解答

Answer 1

#include<stdio.h>
#include<math.h>
#include<conio.h>
#include<stdlib.h>
int main() {
char zifu[50] = {0};
int choice = 0;
long n = 0;
start:
printf("****************************************\n");
printf(" 1、求整数n的立方 \n");
printf(" 2、求整数n的阶乘 \n");
printf(" 3、求1+2+....+n的和 \n");
printf(" 4、结束程序 \n");
printf("****************************************\n");
zifu[0] = getchar();
choice = atoi(zifu);
switch (choice) {
case 1:
printf("输入n:"); scanf("%s",zifu); n = atoi(zifu);
for (int i = 0; i < 3; i++) { n *= n; } printf("n=%d",n); getch();
break;
case 2:
printf("输入n:"); scanf("%s", zifu); n = atoi(zifu);
for (int i = n - 1; i > 0;i--) {
n *= i; } printf("n=%d",n); break;
case 3:
printf("输入n:"); scanf("%s", zifu); n = atoi(zifu);
for (int i = n - 1; i > 0; i--) {
n += i; } printf("n=%d", n); break;
case 4:exit(0); break;
default:system("cls");/*清屏*/ goto start; break; } return 0;}