#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;
        int cnt_repeat = 0;
        for(int j = i; j < ss; j++ ){
            if(moves[j] == '+'){
                int temp = ++values[coords[j]];
                if(temp == 1) cnt_repeat++;
                else if(temp == 0) cnt_repeat--;
            } else {
                int temp = --values[coords[j]];
                if(temp == -1) cnt_repeat++;
                else if(temp == 0) cnt_repeat--;
            }
            if(cnt_repeat == 0) return "NOT VALID";
        }
    }
    return "VALID";
}

<%:testing-code%>
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