Mai intai trebuie sa te autentifici.
Cod sursa(job #1309558)
| Utilizator | Data | 5 ianuarie 2015 20:48:39 | |
|---|---|---|---|
| Problema | Evaluarea unei expresii | Scor | 100 |
| Compilator | cpp | Status | done |
| Runda | Arhiva educationala | Marime | 1 kb |
#include<fstream>
#include<cstring>
using namespace std;
ifstream fin("evaluare.in");
ofstream fout("evaluare.out");
int i;
char s[100010];
int expresie();
int termen();
int factor();
int expresie(){
int r;
r=termen();
while(s[i]=='+' || s[i]=='-'){
if(s[i]=='+'){
i++;
r+=termen();
}else{
i++;
r-=termen();
}
}
return r;
}
int termen(){
int r;
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*=10;
r+=s[i]-'0';
i++;
}
}
return r;
}
int main(){
fin>>s+1;
i=1;
fout<<expresie();
return 0;
}
