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#include<bits/stdc++.h>
using namespace std;
#define f first
#define s second
#define PB push_back
typedef long long ll;
typedef long double ld;
#define REP(x,y) for(int x=0;x<(y);x++)
#define ROF(x,y) for(int x=(y);x>0;x--)
#define FOR(x,z,y) for(int x=(z);x<=(y);x++)
#define INT(x) int x;scanf("%d",&x)
#define LL(x) ll x;scanf("%lld",&x)
#define CZ(x) char x;scanf(" %c",&x)
typedef pair<int,int> pii;
typedef pair<int,pii> piii;

const int MAX_N =  300005;

set<pii> support_set;
set<pii> target;
set<pii> edges;
vector<int> adj[MAX_N], adj2[MAX_N];
bool visited[MAX_N];
vector<pii> to_add, to_remove;

void build_support(int root, int current){
    if(visited[current]) return;
    visited[current]=true;
    pii p = {min(current,root),max(current,root)};
    support_set.insert(p);
    if(!edges.contains(p)){
        to_add.PB(p);
        //printf("+ %d %d\n",p.f,p.s);
    }
    for(int i:adj[current]){
        build_support(root,i);
    }
}

void remove_support(int root, int current){
    if(!visited[current]) return;
    visited[current]=false;
    for(int i:adj2[current]){
        remove_support(root,i);
    }
    pii p = {min(current,root),max(current,root)};
    if(!target.contains(p) && support_set.contains(p)){
        //printf("- %d %d\n",p.f,p.s);
        to_remove.PB(p);
        support_set.erase(p);
    }
}

int main(){
    INT(n);INT(m);
    REP(i,m){
        INT(a); INT(b);
        adj[a].PB(b);
        adj[b].PB(a);
        edges.insert({min(a,b),max(a,b)});
    }
    INT(k);
    REP(i,k){
        INT(a); INT(b);
        adj2[a].PB(b);
        adj2[b].PB(a);
        target.insert({min(a,b),max(a,b)});
    }
    int root=1;
    FOR(i,2,n){
        if(adj[i].size()>adj[root].size()){
            root=i;
        }
    }
    visited[root]=true;
    for(int i:adj[root]){
        build_support(root,i);
    }
    for(pii p:target){
        if(!support_set.contains(p) && !edges.contains(p)){
            to_add.PB(p);
            //printf("+ %d %d\n",p.f,p.s);
        }
    }
    for(pii p:edges){
        if(!target.contains(p) && !support_set.contains(p)){
            to_remove.PB(p);
            //printf("- %d %d\n",p.f,p.s);
        }
    }
    visited[root]=false;
    for(int i:adj2[root]){
        remove_support(root,i);
    }
    printf("%ld\n",to_add.size()+to_remove.size());
    for(pii p:to_add){
        printf("+ %d %d\n",p.f,p.s);
    }
    for(pii p:to_remove){
        printf("- %d %d\n",p.f,p.s);
    }
}