#include<bits/stdc++.h>
//ios::sync_with_stdio(false);cin.tie(0);
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef pair<pii,int> ppii;
typedef pair<int,pii> pipi;
typedef pair<ll,ll> pll;
typedef pair<pll,ll> ppll;
typedef pair<ll,pll> plpl;
typedef tuple<ll,ll,ll> tl;
ll mod=1000000007;
ll mod2=998244353;
ll mod3=1000003;
ll mod4=998244853;
ll inf=1000000000000000000;
double pi=2*acos(0);
#define rep(i,m,n) for(ll i=m;i<n;i++)
#define rrep(i,n,m) for(ll i=n;i>=m;i--)
int dh[4]={1,-1,0,0};
int dw[4]={0,0,1,-1};
int ddh[8]={-1,-1,-1,0,0,1,1,1};
int ddw[8]={-1,0,1,-1,1,-1,0,1};
ll lmax(ll a,ll b){
    if(a<b)return b;
    else return a;
}
ll lmin(ll a,ll b){
    if(a<b)return a;
    else return b;
}
ll gcd(ll a,ll b){
    if(a<b)swap(a,b);
    if(b==0)return a;
    if(a%b==0)return b;
    return gcd(b,a%b);
}
ll Pow(ll n,ll k){
    ll ret=1;
    ll now=n;
    while(k>0){
        if(k&1)ret*=now;
        now*=now;
        k/=2;
    }
    return ret;
}
ll par[800010];
ll len[800010];
void init(ll n){
  for(int i=0;i<n;i++){
    par[i]=i;
    len[i]=0;
  }
}
ll root(ll n){
  if(par[n]==n)return n;
  return par[n]=root(par[n]);
}
void unit(ll a,ll b){
  a=root(a);
  b=root(b);
  if(a==b)return;
  if(len[a]<len[b]){
    par[a]=b;
  }
  else{
    par[b]=a;
    if(len[a]==len[b])len[a]++;
  }
}
ll ne;

vector<ll> vn[800010];
ll par2[60][800010];
ll dep[800010];
void lcadfs(ll v,ll p,ll d){
  par2[0][v]=p;
  dep[v]=d;
  for(ll i=0;i<vn[v].size();i++){
    if(vn[v][i]!=p)lcadfs(vn[v][i],v,d+1);
  }
}
void lcainit(ll n){
  lcadfs(ne,-1,0);
  for(ll i=0;i<59;i++){
    for(ll j=1;j<=n;j++){
      if(par2[i][j]<0)par2[i+1][j]=-1;
      else par2[i+1][j]=par2[i][par2[i][j]];
    }
  }
}
ll lca(ll u,ll v){
  if(dep[u]>dep[v])swap(u,v);
  for(ll i=0;i<60;i++){
    if((dep[v]-dep[u])>>i&1)v=par2[i][v];
  }
  if(u==v)return u;
  for(ll i=59;i>=0;i--){
    if(par2[i][u]!=par2[i][v]){
      u=par2[i][u];
      v=par2[i][v];
    }
  }
  return par2[0][u];
}
int main(){
    int n,m,q;cin>>n>>m>>q;
    init(n+1);
    vector<int> v[n+1];
    rep(i,0,m){
        int a,b;cin>>a>>b;
        v[a].push_back(b);
        v[b].push_back(a);
        unit(a,b);
    }
    set<int> st;
    rep(i,1,n+1){
        st.insert(root(i));
    }
    int sum[n+1];
    fill(sum,sum+n+1,0);
    int cnt[n+1];
    fill(cnt,cnt+n+1,0);
    int a[q],b[q];
    rep(i,0,q){
        cin>>a[i]>>b[i];
        int f=root(a[i]),g=root(b[i]);
        if(f==g)continue;
        cnt[a[i]]++;
        cnt[b[i]]++;
        sum[f]++;
        sum[g]++;
    }
    vector<int> air;
    for(auto itr=st.begin();itr!=st.end();itr++){
        int rr=*itr;
        //cout<<rr<<endl;
        if(sum[rr]==0){
            air.push_back(rr);
            continue;
        }
        unordered_map<int,int> parr,dp,cnn;
        parr[rr]=-1;
        queue<int> q;
        q.push(rr);
        queue<int> qq;
        while(q.size()>0){
            int now=q.front();q.pop();
            int y=0;
            rep(j,0,v[now].size()){
                int nee=v[now][j];
                if(nee==parr[now])continue;
                y=1;
                parr[nee]=now;
                q.push(nee);
            }
            if(y==0)qq.push(now);
        }
        
        while(qq.size()>0){
            int now=qq.front();qq.pop();
            dp[now]=cnt[now];
            rep(j,0,v[now].size())dp[now]+=dp[v[now][j]];
            if(dp[now]*2>=sum[rr]){
                air.push_back(now);
                break;
            }
            int rrr=parr[now];
            cnn[rrr]++;
            if(rrr==rr){
                if(cnn[rrr]==v[rrr].size())qq.push(rrr);
            }
            else{
                if(cnn[rrr]==v[rrr].size()-1)qq.push(rrr);
            }
        }
    }
    vector<pii> vd[n+1];
    rep(i,1,n+1){
        rep(j,0,v[i].size()){
            int nee=v[i][j];
            vd[i].push_back({nee,1});
            vn[i].push_back(nee);
        }
    }
    rep(i,0,air.size()-1){
        int f=air[i];
        int g=air[i+1];
        vd[f].push_back({g,0});
        vd[g].push_back({f,0});
        vn[f].push_back(g);
        vn[g].push_back(f);
    }
    ne=1;
    lcainit(n);
    ll dis[n+1];
    fill(dis,dis+n+1,1000000000);
    dis[1]=0;
    priority_queue<pii,vector<pii>,greater<pii>> qd;
    qd.push({0,1});
    while(qd.size()>0){
        pii p=qd.top();qd.pop();
        int now=p.second;
        rep(i,0,vd[now].size()){
            int nee=vd[now][i].first;
            if(dis[nee]<100000000)continue;
            dis[nee]=dis[now]+vd[now][i].second;
            qd.push({dis[nee],nee});
        }
    }
    //rep(i,1,n+1)cout<<dis[i]<<" ";
    ll ans=0;
    rep(i,0,q){
        int c=lca(a[i],b[i]);
        //cout<<c<<endl;
        ll suu=dis[a[i]]+dis[b[i]]-dis[c]*2;
        ans+=suu;
    }
    cout<<ans<<endl;
}