ACM-ICPC Regionals South Africa 2011 - erraticants

/*
 *  @author: WhiZTiM
 *  @date: 5th May, 2014
 *  @description: ACM-ICPC Regionals South Africa 2011
 */
#include <iostream>
#include <vector>
#include <unordered_set>
using namespace std;
typedef std::vector<char> vchar;
typedef std::vector<int> vint;

struct Coord
{
    int x; int y; int dist;
    bool operator == (const Coord lhs) const
    { return x == lhs.x && y == lhs.y; }
};

namespace std {
    template<>
    struct hash<Coord>
    {
        size_t operator() (const Coord coord) const
        {   return hash<int>()(coord.x) + hash<int>()(coord.y); }
    };
}

void MoveToCordinate_inplace(char direction, Coord& coord)
{
    coord.dist += 1;
    switch(direction)
    {
        case 'N':
            coord.y += 1;
            break;
        case 'E':
            coord.x += 1;
            break;
        case 'S':
            coord.y -= 1;
            break;
        case 'W':
            coord.x -= 1;
            break;
        default:
            //coord.dist -= 1;
            break;
    }
}

int GetShortestMoves(const vchar& inputs)
{
    unordered_set<Coord> pathPoints;
    Coord prev = {0, 0, 0};
    pathPoints.insert(prev);

    for(auto ch : inputs)
    {
        MoveToCordinate_inplace(ch, prev);
        auto pIter = pathPoints.find(prev);
        if (pIter != pathPoints.end())
            prev.dist = pIter->dist;
        else
            pathPoints.insert(prev);
    }

    return prev.dist;
}

vchar GetNextInputSet(int moves)
{
    vchar rtn(moves);
    for(int i = 0; i < moves; i++)
        cin >> rtn[i];
    return rtn;
}

int main()
{
    std::ios::sync_with_stdio(false);
    int numPaths;
    cin >> numPaths;
    vint answers(numPaths);
    for(int i = 0; i < numPaths; i++) {
        int moves;
        cin >> moves;
        answers[i] = GetShortestMoves( GetNextInputSet(moves) );
    }

    for(auto i : answers)
        cout << i << "\n";

    return 0;
}