Cf 7C line (Extended Euclidean linear equation)

Link:

Http://codeforces.com/problemset/problem/7/C

Question:

Given the equation ax found + identified by formula + found C numbers = 0. where A, B, and C are known, X and Y are obtained.

Analysis and Summary:

Extends the template of Euclidean algorithms. This algorithm can be found in several books or on the Internet.

This algorithm is used to obtain the linear equation AX + by = gcd (A, B );

Then, this equation can be converted:

Ax + by = gcd (A, B)

=> AX + by =-C/Z, where-C/z = gcd (A, B)

=> Ax * z + by * z = C.

X and Y can be obtained by extending the Euclidean algorithm,

Then, we only need to find Z, while Z =-C/gcd (A, B );

Therefore, the final answer x = x * (-C/gcd (A, B), Y = y * (-C/gcd (a, B ));

Code:

#include<iostream>#include<cstdio>#include<cstring>using namespace std;typedef long long LL;const LL INF = 5*1e18;void gcd(LL a, LL b, LL& d,LL& x, LL& y){    if(!b){d=a; x=1; y=0; }    else {gcd(b,a%b,d,y,x); y -= x*(a/b); }}int main(){    LL a,b,c,d,x,y;    cin >> a >> b >> c;    gcd(a,b,d,x,y);    if(c%d != 0)        puts("-1");    else         cout << -x*(c/d) << " " << -y*(c/d) << endl;    return 0;}

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Original Http://blog.csdn.net/shuangde800,
D_double (reprinted please mark)