C++ :

#include<iostream>
using namespace std;
int main()
{
    int i=35,j=94,a=0,b=0;
    b=(j-2*i)/2;
    a=i-b;
    cout<<a<<' '<<b;
    return 0;
}

Pascal :

program p2680;
var
  i,j:longint;
begin
  for i:=1 to 35 do
  for j:=1 to 35 do
    begin
      if (i+j=35) and (2*i+4*j=94) then
        writeln(i,' ',j);;
    end;
end.

Java :

import java.util.Scanner;
public class Main{
    public static void main(String [] args){
        // 设x 为鸡的个数，y 为兔子的个数
        // x+y=35;
        // 2*x+4*y=94;
        for(int x=0;x<=35;x++){
            int y=35-x;
            if(2*x+4*y==94){
                System.out.printf("%d %d\n",x,y);
            }
        }
    }
}