数组模拟计算大数阶乘

coding>C++
489 词

C++

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#include <iostream>

const int MAXSIZE=10000;
using namespace std;

void factorial(int n) {
    int result[MAXSIZE];
    result[0] = 1;
    int pos = 0;
    for (int i = 1; i <= n; ++i) {
        int carry = 0;
        for (int j = 0; j <= pos; ++j) {
            int tmp = result[j] * i + carry;
            result[j] = tmp % 10;
            carry = tmp / 10;
        }
        while (carry > 0) {
            result[++pos] = carry % 10;
            carry /= 10;
        }
    }
    for (int i = pos; i >= 0; --i) std::cout << result[i];
}
int main(){
    int n;
    cin >> n;
    factorial(n);
}