Cod sursa(job #1467266)

Utilizator SilviuIIon Silviu SilviuI Data 3 august 2015 09:10:40
Problema Evaluarea unei expresii Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 1.3 kb
#include <stdio.h>
#include <iostream>
#include <cstring>
#include <stdlib.h>
#include <time.h>
#include <bitset>
#include <string>
#include <vector>
#include <math.h>
#include <stack>
#include <queue>
#include <list>
#include <set>
#include <limits.h>
#include <algorithm>
#include <deque>
#define nmax 100010
using namespace std;
int n,i;
char s[nmax];
int eval();
int termen();
int factor();
int eval()
{
    int x=termen();
    while (i<=n && (s[i]=='+' || s[i]=='-')){
        switch (s[i]) {
            case '+':{ i++; x=x+termen(); break; }
            case '-':{ i++; x=x-termen(); break; }
        }
    }
    return x;
}
int termen()
{
    int x=factor();
    while (i<=n && (s[i]=='*' || s[i]=='/')) {
        switch (s[i]) {
            case '*':{ i++; x=x*factor(); break; }
            case '/':{ i++; x=x/factor(); break; }
        }
    }
    return x;
}
int factor()
{
    int x;
    if (s[i]=='(')
    {
        i++;
        x=eval();
        i++;
    } else
    {
        x=0;
        while (i<=n && (s[i]>='0' && s[i]<='9')) {
            x=x*10+s[i]-48; i++;
        }
    }
    return x;
}
int main() {
freopen("evaluare.in","r",stdin);
freopen("evaluare.out","w",stdout):
gets(s+1); n=strlen(s+1); i=1;
printf("%d\n",eval());
return 0;
}