Mai intai trebuie sa te autentifici.
Cod sursa(job #3170372)
| Utilizator | 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;
}
