Mai intai trebuie sa te autentifici.
Cod sursa(job #1330653)
Utilizator | Data | 30 ianuarie 2015 20:53:58 | |
---|---|---|---|
Problema | Evaluarea unei expresii | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.96 kb |
#include <fstream>
using namespace std;
ifstream fin("evaluare.in");
ofstream fout("evaluare.out");
int i;
char s[100002];
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=0;
if(s[i]=='('){
i++;
r=expresie();
i++;
}
else{
while(s[i]>='0' && s[i]<='9'){
r=r*10+s[i]-'0';
i++;
}
}
return r;
}
int main(){
fin>>s;
fout<<expresie();
fin.close();fout.close();
return 0;
}