最大公约数

#include <iostream.h>#include <fstream.h>#include <stdio.h>void writeinfile(int n);void main(){int x,y,n;x=25,y=10;n=x%y;while(n!=0){x=y;y=n;n=x%y;}cout<<y;writeinfile(y);}void writeinfile(int n){fstream myfile;myfile.open(" f.txt" ,ios::out);myfile<<n<<endl;myfile.close();}