zoj1014 不使用表达式树 ac

#include <iostream>#include <string>using namespace std;void getSubExpr( const string& expr, int idx, string& res);int main(){    char name;    string expr;    string query;    string e, res;    int num[100];    char tmp;    int n;    int x = 0;    while (true)    {          cin>>name;          if (name == '*') break;          if (x) cout<<endl;          x = 1;          cout<<"Expression "<<name<<":"<<endl;          getchar(); getchar();          cin>>expr;          cin>>n;          for (int i = 0; i < n; i++)          {             int t=0;             while(cin>>num[t])             {              cin.get(tmp);                            t++;              if (tmp == '/n') break;             }                          for (int j = 0; j < t; j++)             {                 cout<<"op("<<num[t-1-j]<<",";             }             cout<<name;             for (int j = 0; j < t; j++)             {                 cout<<")";                             }             cout<<"=";                      e = expr;                for (int j=0; j<t; j++)             {                 getSubExpr(e, num[j], res);                 e = res;             }             cout<<res<<endl;          }              }}//使用指定的操作符， 看是否能分开表达式  inline bool process(const string& expr, int idx, string& res, char op){     int n = expr.length();     int parenthese = 0;     int st = 0;     int iCnt = 0;     for (int pos = 0; pos < n; pos++)     {         if ( parenthese==0 && expr[pos] == op )         {                  iCnt++;                  if (iCnt == idx)                  {                         res = expr.substr(st, pos-st);                         return true;                  }                  st = pos+1;         } else if ( expr[pos] == '(' )   parenthese++;         else if(expr[pos] == ')') parenthese--;     }     if (iCnt)     {           res = expr.substr(st); return true;     }     return false;}void getSubExpr( const string& expr, int idx, string& res){          int n = expr.length();          if (process(expr, idx, res, '+')) return;     if (process(expr, idx, res, '*')) return;     if (process(expr, idx, res, '^')) return;    //注意一定要最后判断括号, 它优先级最高     if (expr[0] == '(' && expr[n-1]==')')     {        res = expr.substr(1, n-2);        return;     }     res = expr;}