[Ｃ++] 期中考古-1!+3!+5!+....+49!

[sb0917 (ＱＱ)]

#include <iostream>
#include <iomanip>
using namespace std;

int main()
{
    double sum = 0;
    double level = 1;
    int i = 1;
    int j = 1;

    while(i < 50)
    {
        while(j <= i)
        {
            level = level*(double)j;
            j++;
        }
        sum = sum + level;
        level = 1;
        j = 1;
        i+=2;
    }

    cout << "1! + 3! + 5! + 7! + ...... + 49! =\n"
         << sum << endl;

    system("pause");
    return 0;
}

這是浮點數運算...

所以到最後整個就超不準...

要準的話要用大數運算  有興趣的人可以練習一下

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