花日绯最好看的小说:c++中怎样编1+(1+2)+(1+2++++n)

来源:百度文库 编辑:神马品牌网 时间:2024/04/29 09:27:10

就是从1到n的阶乘之和嘛 ^_^

#include <iostream>

using namespace std;

long sum = 1;
long countall = 1;

int main(int argc, char *argv[])
{
cout << "Please input max N : ";
int iNum;
cin >> iNum;
cout << "User input : " << iNum << endl;

for(int i=2; i<=iNum; i++)
{
sum = sum*i;
countall += sum;
}
cout << "Total value is : " << countall << endl;

return 0;
}

我也来一个
int sum = 0;
for(int i = 1; i <= n; i++)
{
int temp = 0;
for(int j = 1; j <= i; j++)
{
temp += j;
}
sum += temp;
}

基本的看fengwang1982就可以了,我给个初中数学竞赛的公式1+(1+2)+……+(1+2+3+……+n)=n(n+1)(n+2)/6,所以函数如下:
float SumList(int n){
float f=n*(n+1)*(n+2)/6;
return f;
}

我也贴一个^_^
int add(int n)
{
int sumTemp = 0;
int sumTotal = 0;
for (int i=0; i<n; i++)
{
sumTemp += i;
sumTotal += sumTemp;
}
return sumTotal;
}

int total(int n)
{
int i=1;
int sum=0;
while (i<=n)
{
int b=i;
while (i)
{
sum+=b;
b--;
}
i++;
}
return sum;
}

个个都是高手,让我这个初学者看得眼大,
看来我还要好好别把劲!!