分析

C++ 代码

#include<bits/stdc++.h>
using namespace std;

//Tools
#define ffor(i,s,e) for(int i=s;i<e;i++)
#define out(x) cout<<x<<" "
#define nl cout<<endl   //nextline

//vars
stack<int> stk;

//fun
int play();

int main(){

    cout<<play()<<endl;
    return 0;
}
bool isNum(int n){
    //将栈内的两个符号，|用负二代指和左括号用负一代指
    return n>0;
}
int countx(string &str,int s){
    int old=s;
    while(str[s]=='x') ++s;
    return s-old;
}
void PushNum(int n){//数字n待入栈
    if(stk.empty()){
        stk.push(n);
        return ;
    }
    int c=stk.top();
    if(isNum(c)){
        stk.pop();
        PushNum(n+c);//将直接连的数字一直向下合并
    }else{
        stk.push(n);
    }
}

int getMax(){
    int maxV=stk.top();stk.pop();
    while(!stk.empty()&&stk.top()==-2){//下一个是|
        stk.pop();//弹出|
        int n=stk.top();stk.pop();
        maxV=max(maxV,n);
    }

    return maxV;
}

int play(){
    string str;
    cin>>str;

    int n=str.size();
    ffor(i,0,n){
        char now=str[i];
        if(now=='x'){
            int nx=countx(str,i);
            PushNum(nx);
            i+=nx-1;
        }else if(now=='('){
            stk.push(-1);
        }else if(now=='|'){
            stk.push(-2);
        }else{
            int m=getMax();
            if(stk.top()==-1) stk.pop();//弹出左括号
            PushNum(m);
        }

        /*查看栈内情况
        stack<int> t(stk);

        while(!t.empty()){
            if(t.top()==-1) out('(');
            else if(t.top()==-2) out('|');
            else out(t.top());
            t.pop();
        }
        nl;
        */
    }

    return getMax();
}


//  xx(xxx)|(xxxx|x)xxx