Cod sursa(job #2527974)

Utilizator alexandruLAlungu alexandru alexandruLA Data 21 ianuarie 2020 10:43:34
Problema Evaluarea unei expresii Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.39 kb
#include <fstream>

using namespace std;
ifstream f("exp.in");
ofstream g("exp.out");
char s[100001],*p;
int eval();
int termen();
int factor();

int eval(){
    int r=termen();
    while(*p=='+'||*p=='-'){
        if(*p=='+'){
            p++;
            r+=termen();
        }
        else {p++;
        r-=termen();}
    }
    return r;
}
int termen(){
int r=factor();
while(*p=='*'||*p=='/'){
        if(*p=='*'){
            p++;
            r*=factor();
        }
        else {p++;
        r/=factor();}
      }
return r;
}

int factor(){
int r=0;
if(*p=='('){
    p++;
    r=eval();
    p++;
   }

else
    while(*p>='0'&&*p<='9'){
        r=r*10+ *p-'0';
        p++;
    }

return r;
}
int main()
{f.getline(s,3000);

p=s;
int rez=eval();
g<<rez;
    return 0;
}
/*int eval(){
    int r=termen();
    while(*p=='+'||*p=='-'){
        if(*p=='+'){
            p++;
            r+=termen();
        }
        else {p++;
        r-=termen();}
    }
    return r;
}
int termen(){
int r=factor();
while(*p=='*'||*p=='/'){
        if(*p=='*'){
            p++;
            r*=factor();
        }
        else {p++;
        r/=factor();}
      }
return r;
}
int factor(){
int r=0;
if(*p=='('){
    p++;
    r=eval();
    p++;
   }
else {
    while(*p>='0'&&*p<='9'){
        r=r*10+*p-'0';
        p++;
    }
}
return r;
}*/