Cod sursa(job #1020473)
Utilizator | Data | 2 noiembrie 2013 09:50:44 | |
---|---|---|---|
Problema | Evaluarea unei expresii | Scor | 40 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 1.08 kb |
#include <fstream>
using namespace std;
char s[100010], i;
int expresie();
int termen();
int factor();
int expresie()
{
int r=termen();
while(s[i]=='+' || s[i]=='-')
if(s[i]=='+')
{
i++;
r+=termen();
}
else
{
i++;
r-=termen();
}
return r;
}
int termen()
{
int r=factor();
while(s[i]=='*' || s[i]=='/')
if(s[i]=='*')
{
i++;
r*=factor();
}
else
{
i++;
r/=factor();
}
return r;
}
int factor()
{
int r;
if(s[i]=='(')
{
i++;
r=expresie();
i++;
}
else
{
r=0;
while(s[i]>='0' && s[i]<='9')
{
r=r*10+s[i]-'0';
i++;
}
}
return r;
}
int main()
{
ifstream f("evaluare.in");
ofstream g("evaluare.out");
f>>s;
g<<expresie();
f.close();
g.close();
return 0;
}