hdu2669扩展欧几里得

赤裸裸的,直接贴代码。。不过注意题目要求X非负,所以最后还要再处理一下。。

/*
 * hdu2669/win.cpp
 * Created on: 2012-7-6
 * Author    : ben
 */
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <ctime>
#include <iostream>
#include <algorithm>
#include <queue>
#include <set>
#include <map>
#include <stack>
#include <string>
#include <vector>
#include <deque>
#include <list>
#include <functional>
#include <numeric>
#include <cctype>
using namespace std;

int gcd(int m, int n) {
    int r = m % n;
    while (r) {
        m = n;
        n = r;
        r = m % n;
    }
    return n;
}

int extend_gcd(int a, int b, int &x, int &y) {
    int d, xx;
    if (b == 0) {
        x = 1, y = 0;
        return a;
    }
    d = extend_gcd(b, a % b, x, y);
    xx = x;
    x = y;
    y = xx - a / b * y;
    return d;
}

int main() {
#ifndef ONLINE_JUDGE
    freopen("data.in", "r", stdin);
#endif
    int m, n;
    while(scanf("%d%d", &m, &n) == 2) {
        if(gcd(m, n) > 1) {
            puts("sorry");
        } else {
            int x, y;
            extend_gcd(m, n, x, y);
            while(x < 0) {
                x += n;
                y -= m;
            }
            printf("%d %d\n", x, y);
        }
    }
    return 0;
}
posted @ 2012-07-06 15:01  moonbay  阅读(142)  评论(0编辑  收藏  举报