C語(yǔ)言編程求1X2X3····Xn所得的數(shù)末尾有多少個(gè)零

參見(jiàn)大數(shù)的階乘
https://blog.51cto.com/14232799/2365277

此次的程序與大數(shù)階乘相似，只改變了數(shù)組的輸出順序，以及添加了計(jì)數(shù)器用來(lái)數(shù)出末尾有多少個(gè)0.

首先定義調(diào)用函數(shù)into

int into(int k, int x[], int * length)
{
    int n, temp, jw = 0;//temp臨時(shí)變量，jw為一次計(jì)算結(jié)果的進(jìn)位
    for (n = 0; n <= *length; n++)
    {
        temp = x[n] * k + jw;
        x[n] = temp % 10;
        jw = temp / 10;
    }
    while (jw)
    {
        x[n] = jw % 10;//當(dāng)有進(jìn)位時(shí)存入進(jìn)位
        jw = jw / 10;
        n++;//數(shù)組填充長(zhǎng)度變化
    }
    *length = n - 1;//計(jì)算次數(shù)變化
    return 0;
}

編輯主函數(shù)，定義各種需要的變量，常規(guī)操作逆序輸出計(jì)算結(jié)果。
最后加上計(jì)數(shù)器即可。

for (i = 2; i <= m; i++)
{
    into(i, x, &p);//調(diào)用函數(shù)計(jì)算結(jié)果存入數(shù)組
}
for (i = 0; i <= p; i++)//輸出計(jì)算結(jié)果末尾0的個(gè)數(shù)
{
    if (x[i] == 0)
        sum++;//累加器
}
for (i = 0; i <=p; i++)//輸出結(jié)果
    printf("%d", x[i]);
printf("\n");
printf("末尾一共%d個(gè)0\n", sum);

完整源代碼：

#include<stdio.h>
#include<stdio.h>

int into(int k, int x[], int * length)
{
    int n, temp, jw = 0;
    for (n = 0; n <= *length; n++)
    {
        temp = x[n] * k + jw;
        x[n] = temp % 10;
        jw = temp / 10;
    }
    while (jw)
    {
        x[n] = jw % 10;
        jw = jw / 10;
        n++;
    }
    *length = n - 1;
    return 0;
}

int main()
{
    int x[100000];
    int i, m;
    int sum=0;
    int p = 0;
    printf("請(qǐng)輸入要計(jì)算的階乘數(shù)：\n");
    scanf("%d", &m);
    x[0] = 1;
    for (i = 2; i <= m; i++)
    {
        into(i, x, &p);
    }
    for (i = 0; i <= p; i++)
    {
        if (x[i] == 0)
            sum++;
    }
    for (i = 0; i <=p; i++)
        printf("%d", x[i]);
    printf("\n");
    printf("末尾一共%d個(gè)0\n", sum);
    system("pause");
    return 0;
}