if statement doesn't work in for loop

Ok i have this problem: if doesn't want to work and i dont know why.

The program is supposed to take from a file some numbers, first indicates the number of numbers on the second line and say what is the minimum and maximum on that line.

#include <iostream>
#include <fstream>


using namespace std;

int main()
{
 ifstream f("file.in");
 ofstream g("file.out");
 int minim,x,maxim,i,n;

 f>>n;
 f>>maxim;
 minim=maxim;

 for(i=2;i<=n;i++){
    f>>x;
    if(minim > x)x=minim;
    if(maxim < x)x=maxim;
 }
    g << "min=" << minim;
    g << "\n" << "max=" << maxim;
    f.close();
    g.close();

return 0;
}

The problem is "if" doesn't work at all.

srry for bad english