Cod sursa(job #3170372)

Utilizator Silviu643Dumitrescu Silviu Florian Silviu643 Data 17 noiembrie 2023 15:05:06
Problema Evaluarea unei expresii Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.86 kb
#include <iostream>
#include <fstream>
#include <cstring>
using namespace std;
ifstream f("evaluare.in");
ofstream g("evaluare.out");
int pos;
string s;
int add();
int fact()
{int x=0;
if(s[pos]=='(')
    {++pos;
    x=add();
    ++pos;
    }
else while(s[pos]>='0' && s[pos]<='9')
    {x*=10;
    x+=s[pos]-'0';
    pos++;
    }
    return x;
}

int mult()
{int res=fact();
while(pos<s.size() && (s[pos]=='*' || s[pos]=='/'))
    {if(s[pos]=='*')
        {++pos;
        res*=fact();
        }
    else
        {++pos;
        res/=fact();
        }
    }
return res;
}

int add()
{int res=mult();
while(pos<s.size() && (s[pos]=='+' || s[pos]=='-'))
    {if(s[pos]=='+')
        {++pos;
        res+=mult();
        }
    else {++pos;
        res-=mult();}
    }
return res;
}

int main()
{f>>s;
g<<add();
return 0;
}