[C++] Drumul minim intre doua puncte. (R.F.)

// Un turist vrea sa calatoreasca din orasul X in orasul Y. Calculati drumul minim

#include <fstream>
#include <iostream>

using namespace std;

ifstream f("A.in");
ofstream g("B.out");

const long val = 99;
int a[50][50], n, i, j, c, v[50], o, p;

void init()
{
    f >> n;
    for(i=1; i<=n; i++)
        for(j=1; j<=n; j++)
            if(i == j)
                a[i][j] = 0;
            else
                a[i][j] = val;
}

void citire()
{
    while(f >> i >> j >> c)
        a[i][j] = c;
    do {
        cout << "Nod plecarea: "; cin >> o;
        cout << "Nod sosire: "; cin >> p;
    } while( o > 0 && o < n && p > 0 && p < n);
}

void afis()
{
    for(i=1; i<=n; i++)
    {
        for(j=1; j<=n; j++)
        {
            g << a[i][j] << "   ";
        }
        g << '\n';
    }
}

void Roy_Floyd()
{
    for(int k=1; k<=n; k++)
        for(i=1; i<=n; i++)
            for(j=1; j<=n; j++)
                if(a[i][k] + a[k][j] < a[i][j])
                    a[i][j] = a[i][k] + a[k][j];
}

int main()
{
    init();
    citire();
    Roy_Floyd();
    afis();
    cout << "* Distanta minima dintre orasele " << o << " - " << p << " este: " << a[o][p];
    return 0;
}