(1)求Sn = a+aa+aaa+aaaa…的值:
#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<stdlib.h>
int main()
{
int a = 0;
int temp = 0;
int sum = 0;
int n = 0;
printf("请输入要计算的项数n以及a的值:");
scanf("%d %d", &n,&a);
for (int i = 0; i < n; ++i)
{
temp = temp * 10 + a;
sum += temp;
}
printf("%d\n", sum);
system("pause");
return 0;
}
(2)求0-999之间的水仙花数:
#include<stdio.h>
#include<stdlib.h>
#include<math.h>
int IsShuixian(int num)
{
int temp = num;
if (num < 100 || num >= 1000)
{
return 0;
}
int num1 = num % 10;
num /= 10;
int num2 = num % 10;
num /= 10;
int num3 = num % 10;
if (pow(num1, 3) + pow(num2, 3) + pow(num3, 3) == temp)
{
return 1;
}
return 0;
}
int main()
{
for (int i = 1; i <= 1000; ++i)
{
if (IsShuixian(i) == 1)
{
printf("%d\n", i);
}
}
system("pause");
return 0;
}
(3)打印半边菱形:
#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<stdlib.h>
void PrintLine(char star)
{
for (int i = 1; i <= star; ++i)
{
printf("*");
}
printf("\n");
}
void PrintLingxing(int n)
{
for (int i = 1; i < n; ++i)
{
PrintLine(2 * i - 1);
}
PrintLine(2 * n - 1);
for (int i = n - 1; i>0; --i)
{
PrintLine(2 * i - 1);
}
}
int main()
{
int n = 0;
printf("请输入菱形中间一行的行号:");
scanf("%d", &n);
PrintLingxing(n);
system("pause");
return 0;
}