11A sursa

#include <bits/stdc++.h>

using namespace std;

int C, n, m, p, a[101][101];
int d[101], viz[101], pred[101], b[101];

ifstream fin("parc.in");
ofstream fout("parc.out");

void Citire()
{
    int x, y, c;
    fin >> n >> m >> C;
    for (int i = 1; i <= n; i++)
        for (int j = i + 1; j <= n; j++)
            a[i][j] = a[j][i] = 1e9;
    for (int i = 1; i <= m; i++)
    {
        fin >> x >> y >> c;
        a[x][y] = a[y][x] = c;
    }
    fin >> p;
    for (int  i = 1; i <= p; i++)
        fin >> b[i];
}


void Dijkstra(int k)
{
    int minim, p, i;
    for (i = 1; i <= n; i++)
    {
        d[i] = 1e9;
        pred[i] = viz[i] = 0;
    }
    d[k] = 0;
    for (int pas = 1; pas < n; pas++)
    {
        minim = 1e9;
        p = 0;
        for (i = 1; i <= n; i++)
            if (d[i] < minim && viz[i] == 0)
            {
                minim = d[i];
                p = i;
            }
        if (minim == 1e9)
            return;
        viz[p] = 1;
        for (i = 1; i <= n; i++)
            if (a[p][i] < 1e9 && d[i] > d[p] + a[p][i])
            {
                d[i] = a[p][i] + d[p];
                pred[i] = p;
            }
    }
}
int main()
{
    int k, minim = 1e9 ;
    Citire();
    Dijkstra(C);
    for (int i = 1; i <= p; i++)
        if (minim > d[b[i]])
        {
            minim = d[b[i]];
            k = b[i];
        }
    fout << k;
    return 0;
}