题目学习——HDUOJ-2669

Romantic

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)

Problem Description

Now tell you two nonnegative integer a and b. Find the nonnegative integer X and integer Y to satisfy X*a + Y*b = 1. If no such answer print "sorry" instead.

 

Input

The input contains multiple test cases.
Each case two nonnegative integer a,b (0<a, b<=2^31)

 

Output

output nonnegative integer X and integer Y, if there are more answers than the X smaller one will be choosed. If no answer put "sorry" instead. 

 

Sample Input

77 5110 4434 79

 

Sample Output

2 -3sorry7 -3

 

Author

yifenfei

#include <iostream>#include <cstdio>#define LL long long intusing namespace std;LL e_gcd(LL a,LL b,LL &x,LL &y){    if(b==0){        x=1;        y=0;        return a;    }    LL ans=e_gcd(b,a%b,x,y);    LL temp=x;    x=y;    y=temp-a/b*y;    return ans;}LL inv(LL a,LL m,LL c){    LL x,y;    LL gcd=e_gcd(a,m,x,y);    if(c%gcd!=0)return -1;    m=c/gcd*m;    if(m<0)m=-m;    LL ans=x%m;    if(ans<=0)ans=ans+m;    return ans;}int main(){    LL a,b,x,y,ans;    while(scanf("%lld%lld",&a,&b)!=EOF){        if((ans=inv(a,b,1))!=-1)printf("%lld %lld\n",ans,(1-ans*a)/b);        else printf("sorry\n");    }    return 0;}