[HBU-DB实验]2-8 符号配对 (20 分)

题目

代码

记由一行标记引发的命案……

#include<bits/stdc++.h>
using namespace std;
int main()
{stack<string> mark;string s;string ch;int num=0;map<string,string> sign;sign["/*"]="*/";sign["("] = ")";sign["{"] = "}";sign["["] = "]";getline(cin,s);num+=s.length();while(s!="."&&num<1000){for(int i=0;i<s.length();i++){int f2=0;  //用来标记是左侧符号or右侧符号string c;switch (s[i]){case '(':case '[':case '{':c=s[i];mark.push(string(c));break;case '/':{if(i<s.length()-1){if(s[i+1]=='*'){c="/*";mark.push("/*");i++;}}break;}case ')':case ']':case '}':f2=1;c=s[i];if(mark.empty()){cout << "NO"<<endl;cout << "?-" << c<<endl;return 0;}ch =mark.top();mark.pop();break;case '*':if(s[i+1]=='/'){f2=1;   //当初就忘了这一条……最后一个点咋也过不去……c="*/";if(mark.empty()){cout << "NO"<<endl;cout << "?-" << c<<endl;return 0;}ch=mark.top();mark.pop();i++;break;}}if(f2==1&&sign[ch]!=c){cout << "NO" << endl;if(mark.empty())      cout << "?-" << c<<endl;else      cout << ch << "-?"<<endl;return 0;}}getline(cin,s);num+=s.length();}if(!mark.empty()){string c = mark.top();cout << "NO"<<endl;cout << c << "-?"<<endl;}else{cout << "YES"<<endl;}
}