p549扩展欧几里得

#include<stdio.h>int euclid(int a,int b,int *x,int *y){    if (b==0)    {        *x=1;        *y=0;        return a;    }    else    {        int d;        d=euclid(b,a%b,x,y);        int tmp;        tmp=*x;        *x=*y;        *y=tmp-(a/b)*(*y);        return d;    }}int main(void){    int a,b,x,y;    scanf("%d%d",&a,&b);    int d;    d=euclid(a,b,&x,&y);    printf("%d=%d*%d+%d*%d\n",d,a,x,b,y);    return 0;}