백준 11404 - 플로이드

백준 11404 - 플로이드
Floyd Warshall Algorithm을 이해할 수 있는 기초 문제였다.

#include <iostream>
#include <vector>
using namespace std;
#define INF 1000000000

int nodes = 0, bus = 0;
int cities[101][101];

void make_input() {
    for (int i = 0; i < bus; i++) {
        int src, dest, d;
        cin >> src >> dest >> d;
        if(cities[src][dest] > d)
            cities[src][dest] = d;
    }
}

void init_map() { // Initialize with INFINITE
    for (int i = 1; i <= nodes; i++) {
        for (int j = 1; j <= nodes; j++) {
            if (i == j) cities[i][j] = 0;
            else cities[i][j] = INF;
        }
    }
}

void floyd_warshall() { // floyid warshall
    for (int sol = 1; sol <= nodes; sol++) {
        for (int i = 1; i <= nodes; i++) {
            for (int j = 1; j <= nodes; j++) {
                if (cities[i][sol] != INF && cities[sol][j] != INF) {
                    cities[i][j] = min(cities[i][j], cities[i][sol] + cities[sol][j]);
                }
            }
        }
    }
}

void print_answer() {
    for (int i = 1; i <= nodes; i++) {
        for (int j = 1; j <= nodes; j++) {
            if (cities[i][j] == INF) cout << 0 << " ";
            else cout << cities[i][j] << " ";
        }
        cout << '\n';
    }
}

int main() {
    cin >> nodes >> bus;

    init_map();
    make_input();
    floyd_warshall();
    print_answer();

    return 0;
}