#include <bits/stdc++.h>
using namespace std;

struct UnionFind {
    vector<int> par;
    vector<int> sz;

    UnionFind(int n=0){
        if(n>0) initialize(n);
    }

    void initialize(int n){
        par.resize(n);
        sz.resize(n);
        for(int i=0; i<n; i++){
            par[i] = i;
            sz[i] = 1;
        }
    }

    int find(int x){
        if(par[x] == x){
            return x;
        }else{
            return par[x] = find(par[x]);
        }
    }

    bool unite(int x, int y){
        x = find(x);
        y = find(y);
        if(x == y) return false;
        if(sz[x] > sz[y]) swap(x, y);
        par[x] = y;
        sz[y] += sz[x];
        return true;
    }

    bool same(int x, int y){
        return find(x) == find(y);
    }

    int size(int x){
        return sz[find(x)];
    }
};

struct LCA{
    static const int BITLEN_MAX = 20;
    vector<int> parent[BITLEN_MAX];
    vector<int> depth;
    int bitlen;

    LCA(int N, vector<vector<int>>& edges){
        int root = 0;
        bitlen = 1;
        while((1<<bitlen) < N) bitlen += 1;
        for(int i=0; i<bitlen; i++) parent[i].resize(N);
        depth.resize(N, -1);

        dfs(root, -1, 0, edges);
        for(int k=0; k<bitlen-1; k++){
            for(int v=0; v<N; v++){
                if(depth[v] == -1) continue;
                if(parent[k][v] < 0){
                    parent[k+1][v] = -1;
                }else{
                    parent[k+1][v] = parent[k][parent[k][v]];
                }
            }
        }
    }

    void dfs(int v, int p, int d, vector<vector<int>>& edges){
        parent[0][v] = p;
        depth[v] = d;
        for(auto u : edges[v]){
            if(u != p) dfs(u, v, d+1, edges);
        }
    }

    int calc_lca(int u, int v){
        if(depth[u] > depth[v]) swap(u, v);
        for(int k=0; k<bitlen; k++){
            if( ((depth[v]-depth[u]) >> k) & 1 ) v = parent[k][v];
        }
        if(u == v) return u;
        for(int k=bitlen-1; k>=0; k--){
            if(parent[k][u] != parent[k][v]){
                u = parent[k][u];
                v = parent[k][v];
            }
        }
        return parent[0][u];
    }

    int calc_dist(int u, int v){
        int l = calc_lca(u, v);
        return depth[u] + depth[v] - depth[l]*2;
    }
};

vector<int64_t> dp, num;
void dfs(int i, int p, vector<int>& W, vector<vector<int>>& E){
    num[i] = W[i];
    for(int j : E[i]) if(j != p){
        dfs(j, i, W, E);
        num[i] += num[j];
        dp[i] += dp[j] + num[j];
    }
}
void dfs2(int i, int p, vector<int>& W, vector<vector<int>>& E, int64_t v, int n, int64_t& ans){
    ans = min(ans, dp[i] + v);
    for(int j : E[i]) if(j != p){
        int n2 = num[i] - num[j] + n;
        int64_t v2 = dp[i] - (dp[j] + num[j]) + v + n2;
        dfs2(j, i, W, E, v2, n2, ans);
    }
}

int64_t calc(vector<int>& W, vector<vector<int>>& E){
    int sz = W.size();
    dp = vector<int64_t>(sz);
    num = vector<int64_t>(sz);
    dfs(0, -1, W, E);
    int64_t ans = 1e18;
    dfs2(0, -1, W, E, 0, 0, ans);
    // for(int a : W) cerr << a << " ";
    // cerr << endl;
    // cerr << ans << endl;
    return ans;
}

int main(){
    int N, M, Q;
    cin >> N >> M >> Q;
    vector<int> edges[100000];
    UnionFind uf(N);
    for(int i=0; i<M; i++){
        int a, b;
        cin >> a >> b;
        a--; b--;
        edges[a].push_back(b);
        edges[b].push_back(a);
        uf.unite(a, b);
    }
    
    vector<int> group(N, -1), pos(N);
    vector<vector<int>> vs;
    for(int i=0; i<N; i++){
        int r = uf.find(i);
        if(group[r] == -1){
            group[r] = vs.size();
            vs.push_back({});
        }
        group[i] = group[r];
        pos[i] = vs[group[r]].size();
        vs[group[i]].push_back(i);
    }
    int G = vs.size();

    vector<int> sz(G);
    vector<vector<int>> W(G);
    vector<vector<vector<int>>> E(G);
    vector<vector<pair<int, int>>> sames(G);
    for(int i=0; i<G; i++){
        sz[i] = vs[i].size();
        W[i].resize(sz[i]);
        E[i].resize(sz[i]);
    }
    for(int i=0; i<N; i++) for(int j : edges[i]) E[group[i]][pos[i]].push_back(pos[j]);
    for(int i=0; i<Q; i++){
        int a, b;
        cin >> a >> b;
        a--; b--;
        if(uf.same(a, b)){
            sames[group[a]].emplace_back(pos[a], pos[b]);
        }else{
            W[group[a]][pos[a]]++;
            W[group[b]][pos[b]]++;
        }
    }

    int64_t ans = 0;
    for(int g=0; g<G; g++){
        ans += calc(W[g], E[g]);
        LCA lca(sz[g], E[g]);
        for(auto& p : sames[g]) ans += lca.calc_dist(p.first, p.second);
    }
    cout << ans << endl;
    return 0;
}