tap17/j.cpp

//touch {a..m}.in; tee {a..m}.cpp < template.cpp
#include <bits/stdc++.h>
using namespace std;
#define forr(i,a,b) for(int i=(a); i<(b); i++)
#define forn(i,n) forr(i,0,n)
#define sz(c) ((int)c.size())
#define zero(v) memset(v, 0, sizeof(v))
#define forall(it,v) for(auto it=v.begin();it!=v.end();++it)
#define pb push_back
#define fst first
#define snd second
typedef long long ll;
typedef pair<int,int> ii;
#define dforn(i,n) for(int i=n-1; i>=0; i--)
#define dprint(v) cout << #v"=" << v << endl //;)

#define INF (1e18+1)
#define N 100
#define M 20

map <string, int> mapi;
vector <int> v[N*M];

bool cmp (vector <int> v1, vector <int> v2){
    forn (i, (int)v1.size()){
        if (v1[i] < v2[i]) return true;
        if (v1[i] > v2[i]) return false;
    }
    return false;
}

bool puedenSerNombres (vector <int> v1, vector <int> v2){
    forn (i, (int)v1.size()){
        if (!(v1[i] ^ v2[i])) return false;
    }
    return true;
}

bool todosUnos (vector <int> v){
    forn (i, (int)v.size())
        if (!v[i]) return false;
    return true;
}

int main(){
    int n,m;
    cin >> n >> m;
    int contador = 0;
    forn (i,n) forn (j,m){
        string s;
        cin >> s;
        if (mapi.count(s) == 0){
            v[contador].resize(n);
            mapi[s] = contador++;
        }
        int number = mapi[s];

        v[number][i] = 1;
    }
        sort(v,v+contador, cmp);
        int i = 0, j = contador - 1;
        bool rta = true;
        while (i <= j){
            if (todosUnos (v[j])) {
                j--;
            }
            else if (puedenSerNombres (v[i], v[j])){
                i++;
                j--;
            }
            else{
                rta = false;
                break;
            }
        }

        cout << (rta?'S':'N') << endl;

    return 0;
}