#include <cstdio>
#include <iostream>
#include <algorithm>
#include <cstring>
#include <cmath>
#include <vector>
#define pb push_back

using namespace std;

vector<int>zeit, fst;
string dani[]={"subota", "nedjelja", "ponedjeljak", "utorak", "srijeda", "cetvrtak", "petak"};

int main(){
    int a, b, c, d;
    char x;
    for(int i=0; i<4; i++){
        cin >> a >> x >> b;
        zeit.pb(a*60+b);
    }
    if(zeit[2]>zeit[3]){ a=zeit[0]; b=zeit[2]; c=zeit[1]; d=zeit[3]; }
    if(zeit[2]<zeit[3]){ a=zeit[1]; b=zeit[3]; c=zeit[0]; d=zeit[2]; }
    int found = 0, sol, check=0;
    while(a<1008000){ a+=b; fst.pb(a); }
    while(c<1008000){
        c+=d;
        for(int i=check; i<fst.size(); i++){
            if(c==fst[i]){
                found = 1;
                sol = c;
                break;}
            if(c<fst[i]){check = i-1; break; }
        }
        if(found) break;
    }
    b=sol%60; a=(sol%1440-b)/60;
    if(!found) cout << "nikad";
    else{
        cout << dani[sol%10080/1440] << endl;
        if(a<10) cout << 0 << a << ":";
        else cout << a << ":";
        if(b<10) cout << 0 << b << endl;
        else cout << b << endl;
    }



    return 0;
}