#include<stdio.h>
#include<stdlib.h>

#define SIZE 1024*128

int number_of_nodes;
int number_of_merchants;
int path[SIZE][1024];
int path2[SIZE][1024];
int N_N[SIZE][1024];
int tax[SIZE];
int c,rootfound,root,taxsum;

void push_N_N();
int select_root();
void order_nodes();
void expand_to_root();
void remove_verbose_path();
void paytax();

void push_N_N(u,v){
    N_N[u][++N_N[u][0]]=v;
    N_N[v][++N_N[v][0]]=u;
}
int select_root(){
    int i,r,max=0;
    for (i=1;i<=number_of_nodes;i++)
        if (N_N[i][0]>max){
            max = N_N[i][0];
            r = i;
        }
    return r;
}
void order_nodes(root,parent){
    int i;
    for (i=1;i<=N_N[root][0];i++)
    {
        if (N_N[root][i] == parent) N_N[root][i]*=(-1);
        else order_nodes(N_N[root][i],root);
    }
}

void expand_to_root(u,mer){
    path[mer][++path[mer][0]]=u;
    if (u==root) return;
    int i,ret;
    for (i=1;i<=N_N[u][0];i++){
        ret = -(N_N[u][i]);
        if (ret > 0) expand_to_root(ret,mer);
    }
}
void expand_to_root2(u,mer){
    path2[mer][++path2[mer][0]]=u;
    if (u==root) return;
    int i,ret;
    for (i=1;i<=N_N[u][0];i++){
        ret = -(N_N[u][i]);
        if (ret > 0) expand_to_root2(ret,mer);
    }
}
void remove_verbose_path(mer){
    while(path[mer][--path[mer][0]]==path2[mer][--path2[mer][0]]);
    ++path[mer][0];
}
void paytax(mer){
    int j;
    for (j=1;j<=path[mer][0];j++){
        taxsum+=(++tax[path[mer][j]]);
    }
    for (j=1;j<=path2[mer][0];j++){
        taxsum+=(++tax[path2[mer][j]]);
    }
}


int main(){
    int i,j,k, u,v,mer;
    scanf("%d",&number_of_nodes);
    for (i=1;i<number_of_nodes;i++){
        scanf("%d %d",&u,&v);
        push_N_N(u,v);
    }
    root = select_root();
    order_nodes(root,-1);
    //-----------above OK!!!!
    scanf("%d", &number_of_merchants);
    for (mer=1;mer<=number_of_merchants;mer++){
        scanf("%d %d",&u,&v);
        expand_to_root(u,mer);
        expand_to_root2(v,mer);
        remove_verbose_path(mer);
        paytax(mer);
    }
    printf("%d\n",taxsum);
}