Lưu ý: Các code mẫu dưới đây chỉ mang tính tham khảo và có thể không AC được bài tập này

Code mẫu của flashmt

const fi='';
      fo='';
type int64=longint;
var a,b,c,d,x,y:int64;

procedure rf;
begin
     assign(input,fi);
     reset(input);
     read(a,c,b,d);
     close(input);
end;

function getmax(a,b:int64):int64;
begin
     if a>b then getmax:=a else getmax:=b;
end;

function gcd(m,n:int64):int64;
begin
     m:=abs(m); n:=abs(n);
     repeat
           if m>n then m:=m mod n
           else n:=n mod m;
     until m*n=0;
     gcd:=m+n;
end;

procedure swap(var a,b:int64);
var t:int64;
begin
     t:=a; a:=b; b:=t;
end;

procedure findroot(a,b:int64;var x0,y0:int64);
var r,q,xt,yt,x1,y1:int64;
begin
     x0:=1; y0:=0;
     x1:=0; y1:=1;
     repeat
           q:=a div b;
           r:=a mod b;
           a:=b; b:=r;
           xt:=x0; yt:=y0;
           x0:=x1; y0:=y1;
           x1:=xt-q*x1; y1:=yt-q*y1;
     until b=0;
end;

procedure pr;
var x0,y0,min,max,min1,max1:int64;
begin
     c:=d-c;
     if a=0 then
     begin
          x:=0;
          y:=c div (-b);
          exit;
     end;
     if b=0 then
     begin
          y:=0;
          x:=c div a;
          exit;
     end;
     d:=gcd(a,b);
     a:=a div d;
     b:=b div d;
     c:=c div d;
     findroot(a,b,x0,y0);
     x0:=x0*c; y0:=y0*c;
     if a*x0-b*y0<>c then
     begin
          if a*x0-b*(-y0)=c then y0:=-y0;
          if a*(-x0)-b*y0=c then x0:=-x0;
          if a*(-x0)-b*(-y0)=c then
          begin
               x0:=-x0;
               y0:=-y0;
          end;
     end;
     if (x0>=0) and (y0>=0) then
     begin
          max:=x0 div b;
          max1:=y0 div a;
          max:=getmax(max,max1);
          x0:=x0-max*b;
          y0:=y0-max*a;
     end;
     if (x0<0) and (y0<0) then
     begin
          max:=abs(x0) div b;
          max1:=abs(y0) div a;
          max:=getmax(max,max1);
          x0:=x0+max*b;
          y0:=y0+max*a;
     end;
     if (x0>=0) and (y0<0) then
     begin
          max:=abs(y0) div a;
          x0:=x0+max*b;
          y0:=y0+max*a;
     end;
     if (x0<0) and (y0>=0) then
     begin
          max:=abs(x0) div b;
          x0:=x0+max*b;
          y0:=y0+max*a;
     end;
     if (x0<0) or (y0<0) then
     repeat
           x0:=x0+b;
           y0:=y0+a;
     until (x0>=0) and (y0>=0);
     x:=x0; y:=y0;
end;

procedure wf;
begin
     assign(output,fo);
     rewrite(output);
     write(x,' ',y);
     close(output);
end;

begin
     rf;
     pr;
     wf;
end.

Code mẫu của ladpro98

#include <bits/stdc++.h>

using namespace std;

#define int long long

int bezout(int a, int b) {
    int xa = 1, xb = 0;
    while (b) {
        int q = a / b;
        int r = a - q * b, xr = xa - q * xb;
        a = b; xa = xb;
        b = r; xb = xr;
    }
    return xa;
}

int solve(int a, int b, int c) {
    int g = __gcd(a, b);
    int x = bezout(a, b) * (c / g);
    int p = abs(b / g), q = abs(a / g);
    x = (x % p + p) % p;
    int y = (c - a * x) / b;
    int cur = x + y;
    if (x < 0 || y < 0) cur = -1;
    int yy = (y % q + q) % q;
    int xx = (c - b * yy) / a;
    if (cur == -1 || (min(xx, yy) >= 0 && cur > xx + yy))
        cout << xx << ' ' << yy << endl;
    else
        cout << x << ' ' << y << endl;
}

main() {
    int a1, a2, b1, b2;
    cin >> a1 >> b1 >> a2 >> b2;
    solve(a1, -a2, b2 - b1);
}

Code mẫu của RR

{$R+,Q+}
procedure ee(a,b:int64;var x,y:int64);
var
  x2,y2:int64;
begin
  if (a<b) then ee(b,a,y,x)
  else if (b=0) then
    begin
      x:=1;
      y:=0;
    end
  else
    begin
      ee(b,a mod b,x2,y2);
      x:=y2;
      y:=x2-(a div b)*y2;
    end;
end;
function gcd(a,b:int64):int64;
begin
  if (a=0) or (b=0) then exit(a+b)
  else if a<b then exit(gcd(b,a))
  else exit(gcd(b,a mod b));
end;
var
  d,x1,y1,x2,y2,b,a1,b1,a2,b2,k:int64;
begin
  read(a1,b1,a2,b2);
  d:=gcd(a1,a2);
  b:=(b2-b1) div d;
  ee(a1,a2,y1,y2);
  k:=(y2-y1)*b*d div (a1+a2);
  repeat
    dec(k);
  until (y1-y2)*b+k*(a1+a2) div d<0;
  repeat
    inc(k);
  until (y1-y2)*b+k*(a1+a2) div d>=0;
  writeln(y1*b+k*a2 div d,' ',-y2*b+k*a1 div d);
end.

Code mẫu của hieult

#include<iostream>
#include<cstdio>
#include<cmath>
using namespace std;
typedef long long ll;
ll a,b,c,d,a1,b1,a2,b2,xo, yo,x,y,t;
void Enter(){
     cin >> a1 >> b1 >> a2 >> b2;
}
ll gcd(ll a, ll b){
     while(b>0){
          ll r=a%b;
          a=b;
          b=r;      
     }
     return a;
}
void ee(ll a, ll b, ll &x, ll &y){
     ll x2, y2;
     if(a<b)ee(b,a,x,y); else if(b==0){
             x=1; y=0;            
     }else {
         ee(b,a%b,x2,y2);  
         x=y2;
         y=(ll)(x2-(a/b)*y2);
     }
}
void swap(ll &x, ll &y){
     ll tg;
     tg= x; x=y; y=tg;
}
ll min(ll x, ll y){
     return (x<y)?x:y;
}
void Solve(){
     if(b1>b2){
           a=a2;    
           b=-a1;
           c=b1-b2;
     }else{
         a=a1; 
         b=-a2;
         c=b2-b1;           
     }
     d=gcd(abs(a),abs(b));
     a/=d; b/=d; c/=d;
     ee(abs(a),abs(b),xo,yo);    
     if(abs(a) < abs(b))swap(xo,yo);
     yo=-yo*c; xo*=c; 
     double tmp1=floor((-xo*1.0)/(b*1.0));  
     double tmp2=floor((yo*1.0)/(a*1.0));
     t=min((ll)(tmp1),(ll)(tmp2));
     x=xo+b*t; y=yo-a*t;
       if(a1*x+b1!=a2*y+b2)swap(x,y);
     cout << x << " " << y << endl;
}

int main(){
    Enter();
    Solve();
    return 0;
}