拓展欧几里得

妈妈呀我会写拓展欧几里得了。
 1 #include<iostream>
 2 #include<cstdio>
 3 #include<cmath>
 4 #include<algorithm>
 5 #include<queue>
 6 #include<cstring>
 7 #define PAU putchar(' ')
 8 #define ENT putchar('
')
 9 using namespace std;
10 void exgcd(int a,int b,int&ans,int &x,int &y){
11      if(b==0){ans=a;x=1;y=0;return;}
12      exgcd(b,a%b,ans,x,y);
13      int t=x;x=y;y=t-a/b*y;
14 }
15 inline int read(){
16     int x=0,sig=1;char ch=getchar();
17     while(!isdigit(ch)){if(ch=='-') sig=-1;ch=getchar();}
18     while(isdigit(ch)) x=10*x+ch-'0',ch=getchar();
19     return x*=sig;
20 }
21 inline void write(int x){
22     if(x==0){putchar('0');return;}if(x<0) putchar('-'),x=-x;
23     int len=0,buf[15];while(x) buf[len++]=x%10,x/=10;
24     for(int i=len-1;i>=0;i--) putchar(buf[i]+'0');return;
25 }
26 void init(){
27     int a,b,x,y,ans;
28     a=read();b=read();
29     exgcd(a,b,ans,x,y);
30     write(ans);
31     return;
32 }
33 void work(){
34     return;
35 }
36 void print(){
37     return;
38 }
39 int main(){
40     init();work();print();return 0;
41 }