C :

#include<stdio.h>
char s[] = "OOTTFFSSEN";

void test() {
    int d; scanf("%d", &d);
    while( d ) {
        putchar(s[d%10]);
        d /= 10;
    }
    puts("");
}

int main() {
    int t;
    scanf("%d", &t);
    while( t-- ) test();
    return 0;
}

C++ :

#include<iostream>
using namespace std;
int main()
{
    int T;
    cin>>T;
    char a[10]= {'O','O','T','T','F','F','S','S','E','N'};
    while(T--)
    {
        string s;
        cin>>s;
        for(int i = s.size()-1;i >= 0;i--)
        cout<<a[s[i] - '0'];
        cout<<endl;
    }
    return 0;
}