#include <vector>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <ctime>

using namespace std;

class RouteIntersection {
public:
    string isValid(int, vector <int>, string);
};

string RouteIntersection::isValid(int N, vector <int> coords, string moves) {
    int ss = coords.size();
    for(int i = 0; i < ss; i++ ){
        map<int, int> values;
        for(int j = i; j < ss; j++ ){
            if(moves[j] == '+') values[coords[j]]++;
            else values[coords[j]]--;

            bool good = true;
            map<int, int>::iterator it;
            for(it = values.begin(); it != values.end(); it++ ){
                if(it->second) good = false;
            }
            if(good) return "NOT VALID";
        }
    }
    return "VALID";
}

<%:testing-code%>
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