不是求调。本地能过，OJ上RE。求RE可能的原因。

#include<bits/stdc++.h>
using namespace std;
char s[1000005];
int len,w[125];
stack<int> s1;
stack<char> s2;
void calc(){
	char ch=s2.top();
	s2.pop();
	if(ch=='!'){
		s1.top()^=1;
		return;
	}
	int x=s1.top();
	s1.pop();
	if(ch=='&') s1.top()&=x;
	else if(ch=='|') s1.top()|=x;
}
signed main(){
	freopen("boolean.in","r",stdin);
	freopen("boolean.out","w",stdout);
	scanf("%s",s+1);
	len=strlen(s+1);
	w['|']=1,w['&']=2,w['!']=3;
	for(int i=1;i<=len;i++){
		if(s[i]==' ') continue;
		if(s[i]=='F') s1.push(0);
		else if(s[i]=='V') s1.push(1);
		else if(s[i]==')'){
			while(s2.top()!='(') calc();
			s2.pop();
		}else if(s[i]=='('||s[i]=='!') s2.push(s[i]);
		else{
			while(s2.size()&&w[s[i]]<=w[s2.top()]) calc();
			s2.push(s[i]);
		}
	}
	while(s2.size()) calc();
	if(s1.top()) puts("V");
	else puts("F");
	return 0;
}