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#include <cstdio>
#include <vector>
#include <algorithm>
using namespace std;

vector <int> UF;

int ufind (int a) {
    if (UF[a] == a) return a;
    UF[a] = ufind(UF[a]);
    return UF[a];
}

bool Union (int a, int b) {
    int ufa = ufind(a), ufb = ufind(b);
    if (ufa == ufb) return false;

    UF[a] = ufb;
}

int main () {
    int n, m, k;
    scanf ("%d %d %d", &n, &m, &k);

    UF.resize(n+1, 0);
    for (int i=1; i<=n; i++) UF[i] = i;

    int mass [n+1];
    for (int i=1; i<=n; i++) {
        int x; scanf ("%d" ,&x);
        mass[i] = x;
    }

    for (int i=0; i<m; i++) {
        int a, b; scanf ("%d %d", &a, &b);
        Union (a, b);
    }

    long long answer = 0;
    for (int i=0; i<k; i++) {
        int a, b; scanf ("%d %d", &a, &b);
        int ufa = ufind(a), ufb = ufind(b);
        if (ufa == ufb) {
            int dmass = min (mass[a], mass[b]);
            mass[a] -= dmass;
            mass[b] -= dmass;
            answer = answer + dmass + dmass;
        }
    }

    printf ("%Ld\n", answer);
    return 0;
}