UVa 11291 - Smeech

Accepted date: 2018-06-17
Run Time: 0.000
Ranking (as of 2018-06-17): 186 out of 391
Language: C++

/*
  UVa 11291 - Smeech

  To build using Visual Studio 2015:
    cl -EHsc -O2 UVa_11291_Smeech.cpp
*/

#include <iostream>
#include <string>
#include <cstdio>
#include <cstdlib>
#include <cstring>
using namespace std;

double smeech(char* ss, char** se)
{
  while (isspace(*ss))
    ss++;
  if (*ss == '(') {
    ss++;
    double p = strtod(ss, se);
    ss = *se;
    double e1 = smeech(ss, se);
    ss = *se;
    double e2 = smeech(ss, se);
    ss = *se;
    while (*ss != ')')
      ss++;
    *se = ss + 1;
    return p * (e1 + e2) + (1.0 - p) * (e1 - e2);
  }
  else
    return strtod(ss, se);
}

int main()
{
  while (true) {
    string s;
    getline(cin, s);
    if (s == "()")
      break;
    char* ss = new char[s.length() + 1];
    strcpy(ss, s.c_str());
    char* se;
    printf("%.2lf\n", smeech(ss, &se));
    delete[] ss;
  }
  return 0;
}