#include<iostream> 
using namespace std;
struct node{
    int lch,rch,fa;
    long long val;
}t[210];
int n;
int tp(char x){
    if(x=='+') return 1;
    if(x=='-') return 2;
    if(x=='*') return 3;
    if(x=='/') return 4;
}

long long dfs(int p){
    if(p<=n) return t[p].val;
    if(t[p].val==1) return dfs(t[p].lch)+dfs(t[p].rch);
    if(t[p].val==2) return dfs(t[p].lch)-dfs(t[p].rch);
    if(t[p].val==3) return dfs(t[p].lch)*dfs(t[p].rch);
    if(t[p].val==4) return dfs(t[p].lch)/dfs(t[p].rch);
}

int main(){
    freopen("expr_tree.in","r",stdin);
    freopen("expr_tree.out","w",stdout);
    
    scanf("%d",&n);
    for(int i=1;i<=n;i++){
        int x;scanf("%d",&x);
        t[i].val=x;
    }
    for(int i=n+1;i<=n*2-1;i++){
        char c;int lc,rc;scanf(" %c%d%d",&c,&lc,&rc);
        t[i].lch=lc;
        t[i].rch=rc;
        t[i].val=tp(c);
        t[lc].fa=t[rc].fa=i;
    }
    int root=1;
    while(t[root].fa) root=t[root].fa;
    
    printf("%lld",dfs(root));
    
    return 0;
}