#include <stdio.h>
//计算1!+2!+3!+......+10!
int main() {
int num = 0;
//int sum = 1;//如果将声明sum放在for循坏外,则在内循环中不会初始赋值
//sum = 1*1
//sum = 1*1*2
//sum = 1*1*2*3
for (int i = 1; i <= 10; i++)
{
int sum = 1;
for (int j = 1; j <= i; j++)
{
sum = sum * j;
}
num += sum;
}
printf("%d\n", num);
return 0;
}
//优化一下
int main() {
int sum = 1;
int num = 0;
for (int i = 1; i <= 10; i++)
{
sum = sum * i;
num += sum;
}
printf("%d\n", num);
return 0;
}
//输入一个数,计算它的阶乘
int main() {
int a = 0;
int num = 1;
scanf("%d", &a);
for (int i = 1; i < a+1; i++)
{
num = num * i;
}
printf("%d\n", num);
return 0;
}