#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cmath>
using namespace std;
#define pa t[x].fa
#define lc t[x].ch[0]
#define rc t[x].ch[1]
const int N=3e4+5;
inline int read(){
char c=getchar();int x=0,f=1;
while(c<‘0‘||c>‘9‘){if(c==‘-‘)f=-1;c=getchar();}
while(c>=‘0‘&&c<=‘9‘){x=x*10+c-‘0‘;c=getchar();}
return x*f;
}
struct node{
int ch[2],fa,rev;
int sum,w;
}t[N];
inline void update(int x){t[x].sum=t[lc].sum+t[rc].sum+t[x].w;}
inline int wh(int x){return t[pa].ch[1]==x;}
inline int isRoot(int x){return t[pa].ch[0]!=x&&t[pa].ch[1]!=x;}
inline void pushDown(int x){
if(t[x].rev){
t[lc].rev^=1;
t[rc].rev^=1;
swap(lc,rc);
t[x].rev=0;
}
}
inline void rotate(int x){
int f=t[x].fa,g=t[f].fa,c=wh(x);
if(!isRoot(f)) t[g].ch[wh(f)]=x;t[x].fa=g;
t[f].ch[c]=t[x].ch[c^1];t[t[f].ch[c]].fa=f;
t[x].ch[c^1]=f;t[f].fa=x;
update(f);update(x);
}
int st[N],top;
inline void splay(int x){
top=0;st[++top]=x;
for(int i=x;!isRoot(i);i=t[i].fa) st[++top]=t[i].fa;
for(int i=top;i>=1;i--) pushDown(st[i]);
for(;!isRoot(x);rotate(x))
if(!isRoot(pa)) rotate(wh(x)==wh(pa)?pa:x);
}
inline void Access(int x){
for(int y=0;x;y=x,x=pa){
splay(x);
rc=y;
update(x);
}
}
inline void MakeRoot(int x){
Access(x);
splay(x);
t[x].rev^=1;
}
inline int FindRoot(int x){
Access(x);
splay(x);
while(lc) x=lc;
return x;
}
inline void Link(int x,int y){
MakeRoot(x);
t[x].fa=y;
splay(x);
}
int n,Q,x,y;
char s[N];
int main(){
//freopen("in.txt","r",stdin);
n=read();
for(int i=1;i<=n;i++) t[i].w=t[i].sum=read();
Q=read();
while(Q--){
scanf("%s",s);x=read();y=read();
if(s[0]==‘b‘){
if(FindRoot(x)==FindRoot(y)) puts("no");
else puts("yes"),Link(x,y);
}else if(s[0]==‘p‘){
t[x].w=y;
//Access(x);
splay(x);
}else{
if(FindRoot(x)!=FindRoot(y)) puts("impossible");
else{
MakeRoot(x);Access(y);splay(y);
printf("%d\n",t[y].sum);
}
}
}
}