Submission #1841458

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Source Code Expand

#include <iostream>
#include <iomanip>
#include <vector>
#include <valarray>
#include <map>
#include <set>
#include <list>
#include <queue>
#include <stack>
#include <bitset>
#include <utility>
#include <numeric>
#include <algorithm>
#include <functional>
#include <complex>
#include <string>
#include <sstream>

#include <cstdio>
#include <cstdlib>
#include <cctype>
#include <cstring>
#include <cmath>

using namespace std;

#define all(c) c.begin(),c.end()
#define repeat(i,n) for(int i=0;i<static_cast<int>(n);i++)
#define debug(x) #x << "=" << (x)
#define dump(x) cerr << debug(x) << " (L:" << __LINE__ << ")"<< endl

typedef long long ll;
typedef vector<int> vi;
typedef vector<vector<int> > vvi;
typedef vector<vector<vector<int> > > vvvi;
typedef vector<string> vs;

template<typename T>
ostream& operator<<(ostream& os, const vector<T>& vec){
    os << "[";
    for(int i = 0; i < vec.size(); i++){
        os << vec[i] << ",";
    }
    os << "]";
    return os;
}

template<typename T>
T input(){
    T t;
    cin >> t;
    return t;
}

template<typename T>
vector<T> input(const int N){
    vector<T> v(N);
    repeat(i,N) cin >> v[i];
    return v;
}

long long gcd(long long a, long long b){
    if(b == 0){
        return a;
    }
    return gcd(b, a % b);
}

long long lcm(long long a, long long b){
    return (a / gcd(a, b)) * b;
}

long long mul(const long long& a, const long long& b, const long long& mod) {
    return ((a % mod) * (b % mod)) % mod;
}

long long power(const long long& x, const long long& y, const long long& mod) {
    if (y == 0) {
        return 1;
    } else if (y == 1) {
        return x % mod;
    } else {
        long long value = power(x, y / 2, mod);
        if (y % 2 == 0) {
            return mul(value, value, mod);
        } else {
            return mul(value, value, mod) * x % mod;
        }
    }
}

long long div(const long long& a, const long long& b, const long long& mod) {
    return mul(a, power(b, mod - 2, mod), mod);
}

map<long long, long long> factorials;
long long factorial(const long long& n, const long long& mod) {
    if (n == 0 || n == 1) {
        return 1;
    }
    if (factorials[n] != 0) {
        return factorials[n];
    }
    factorials[n] = n * factorial(n - 1, mod) % mod;
    return factorials[n] % mod;
}

long long combination(const long long& n, const long long& x, const long long& mod) {
    long long numerator = 1;
    long long denominator = 1;
    repeat(i, x) {
        numerator *= (n - i) % mod;
        numerator %= mod;
        denominator *= (i + 1) % mod;
        denominator %= mod;
    }
    return div(numerator, denominator, mod);
}

struct Node {
    int totalLength;
    int currentHouse;

    Node(int _totalLength, int _currentHouse) {
        totalLength = _totalLength;
        currentHouse = _currentHouse;
    }

    bool operator >(const Node& lhs) const {
        return this->totalLength > lhs.totalLength;
    }
};

int N, M;
int NO_CONNECTION = 10000000;

int findPath(vvi roads, int currentHouse, int nextHouse) {
    if (roads[currentHouse][nextHouse] == NO_CONNECTION) {
        return -1;
    }
    if (nextHouse == 0) {
        return 0;
    }
//    cout << "visiting" << " current: " << currentHouse << " nextHouse: " << nextHouse << endl;
    roads[currentHouse][nextHouse] = NO_CONNECTION;
    roads[nextHouse][currentHouse] = NO_CONNECTION;

    int minimumPath = NO_CONNECTION;
    repeat (i, N) {
        if (i == currentHouse) {
            continue;
        }
        if (roads[nextHouse][i] == NO_CONNECTION) {
//            cout << "No connection between " << currentHouse << " i: " << i << endl;
            continue;
        }
        int restPathLength = findPath(roads, nextHouse, i);
        if (restPathLength != -1) {
            minimumPath = min(minimumPath, roads[nextHouse][i] + restPathLength);
        }
    }
    if (minimumPath != NO_CONNECTION) {
        return minimumPath;
    }

    return -1;
}

int main(){
    cin >> N >> M;

    vvi roads(N, vi(N, NO_CONNECTION));

    int origin, destination, length;
    repeat (i, M) {
        cin >> origin >> destination >> length;
        roads[origin - 1][destination - 1] = length;
        roads[destination - 1][origin - 1] = length;
    }

    int minimum = NO_CONNECTION;

    repeat (i, N) {
        if (i == 0) {
            continue;
        }
        int pathLength = findPath(roads, 0, i);
        if (pathLength != -1) {
            minimum = min(minimum, pathLength + roads[0][i]);
        }
    }
    if (minimum != NO_CONNECTION) {
        cout << minimum << endl;
    } else {
        cout << -1 << endl;
    }
    return 0;
}

Submission Info

Judge Result