Graph/tests/aizu_grl_1_c_floyd.test.cpp

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Last update: 2022-01-13 13:16:22+08:00
Problem: https://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=GRL_1_C

Depends on

Code

#define PROBLEM "https://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=GRL_1_C"

#include "../../template.h"
#include "../floyd.h"

void solve() {
    int n, m; cin >> n >> m;
    vector<vector<ll>> c(n, vector<ll> (n, INF));
    for (int i = 0; i < n; i++) c[i][i] = 0;

    while (m--) {
        int u, v; ll cost; cin >> u >> v >> cost;
        c[u][v] = min(c[u][v], cost);
    }

    Floyd f(n, c);
    for (int i = 0; i < n; i++) {
        if (f.c[i][i] < 0) {
            cout << "NEGATIVE CYCLE" << endl;
            return;
        }
    }
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            if (f.c[i][j] == INF) cout << "INF";
            else cout << f.c[i][j];
            cout << (j == n-1 ? '\n' : ' ');
        }
    }
}

#line 1 "Graph/tests/aizu_grl_1_c_floyd.test.cpp"
#define PROBLEM "https://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=GRL_1_C"

#line 1 "template.h"
#include <bits/stdc++.h>
using namespace std;

#define FOR(i,a,b) for(int i=(a),_b=(b); i<=_b; i++)
#define FORD(i,a,b) for(int i=(a),_b=(b); i>=_b; i--)
#define REP(i,a) for(int i=0,_a=(a); i<_a; i++)
#define EACH(it,a) for(__typeof(a.begin()) it = a.begin(); it != a.end(); ++it)

#define DEBUG(x) { cout << #x << " = "; cout << (x) << endl; }
#define PR(a,n) { cout << #a << " = "; FOR(_,1,n) cout << a[_] << ' '; cout << endl; }
#define PR0(a,n) { cout << #a << " = "; REP(_,n) cout << a[_] << ' '; cout << endl; }

#define sqr(x) ((x) * (x))

// For printing pair, container, etc.
// Copied from https://quangloc99.github.io/2021/07/30/my-CP-debugging-template.html
template<class U, class V> ostream& operator << (ostream& out, const pair<U, V>& p) {
    return out << '(' << p.first << ", " << p.second << ')';
}

template<class Con, class = decltype(begin(declval<Con>()))>
typename enable_if<!is_same<Con, string>::value, ostream&>::type
operator << (ostream& out, const Con& con) {
    out << '{';
    for (auto beg = con.begin(), it = beg; it != con.end(); it++) {
        out << (it == beg ? "" : ", ") << *it;
    }
    return out << '}';
}
template<size_t i, class T> ostream& print_tuple_utils(ostream& out, const T& tup) {
    if constexpr(i == tuple_size<T>::value) return out << ")"; 
    else return print_tuple_utils<i + 1, T>(out << (i ? ", " : "(") << get<i>(tup), tup); 
}
template<class ...U> ostream& operator << (ostream& out, const tuple<U...>& t) {
    return print_tuple_utils<0, tuple<U...>>(out, t);
}

mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
long long get_rand(long long r) {
    return uniform_int_distribution<long long> (0, r-1)(rng);
}

template<typename T>
vector<T> read_vector(int n) {
    vector<T> res(n);
    for (int& x : res) cin >> x;
    return res;
}

void solve();

int main() {
    ios::sync_with_stdio(0); cin.tie(0);
    solve();
    return 0;
}
#line 1 "Graph/floyd.h"
// Tested:
// - https://cses.fi/problemset/task/1672/
// - (trace) https://oj.vnoi.info/problem/floyd
using ll = long long;
const ll INF = 4e18;
struct Floyd {
    Floyd(int _n, const std::vector<std::vector<ll>> _c) : n(_n), c(_c), trace(n) {
        for (int i = 0; i < n; i++) {
            trace[i] = std::vector<int> (n, -1);
            for (int j = 0; j < n; j++) {
                if (c[i][j] == INF) trace[i][j] = -1;
                else trace[i][j] = i;
            }
        }

        for (int k = 0; k < n; k++) {
            for (int i = 0; i < n; i++) {
                for (int j = 0; j < n; j++) {
                    if (c[i][k] != INF && c[k][j] != INF && c[i][j] > c[i][k] + c[k][j]) {
                        c[i][j] = c[i][k] + c[k][j];
                        trace[i][j] = trace[k][j];
                    }
                }
            }
        }
    }

    // Return {distance, path}
    // If no path -> returns {-1, {}}
    std::pair<ll, std::vector<int>> get_path(int start, int target) {
        if (trace[start][target] == -1) return {-1, {}};

        std::vector<int> path;
        for (int u = target; u != start; u = trace[start][u]) {
            path.push_back(u);
        }
        path.push_back(start);
        reverse(path.begin(), path.end());
        return {c[start][target], path};
    }

    int n;
    std::vector<std::vector<ll>> c;
    std::vector<std::vector<int>> trace;
};

#line 5 "Graph/tests/aizu_grl_1_c_floyd.test.cpp"

void solve() {
    int n, m; cin >> n >> m;
    vector<vector<ll>> c(n, vector<ll> (n, INF));
    for (int i = 0; i < n; i++) c[i][i] = 0;

    while (m--) {
        int u, v; ll cost; cin >> u >> v >> cost;
        c[u][v] = min(c[u][v], cost);
    }

    Floyd f(n, c);
    for (int i = 0; i < n; i++) {
        if (f.c[i][i] < 0) {
            cout << "NEGATIVE CYCLE" << endl;
            return;
        }
    }
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            if (f.c[i][j] == INF) cout << "INF";
            else cout << f.c[i][j];
            cout << (j == n-1 ? '\n' : ' ');
        }
    }
}