Cod sursa(job #749849)

Utilizator purevil95Hobana Matei purevil95 Data 19 mai 2012 11:43:05
Problema Evaluarea unei expresii Scor 60
Compilator cpp Status done
Runda Arhiva educationala Marime 0.94 kb
#include<fstream>
#include<string.h>
using namespace std;
fstream in,out;
char s[100001];
int p;
int termen();
int factor();
int expresie()
{
	int sum=termen();
	while(s[p]=='+'||s[p]=='-')
	{
		if(s[p]=='+')
		{
			p++;
			sum+=termen();
		}
		else
		{
			p++;
			sum-=termen();
		}
	}
	return sum;
}
int termen()
{
	int prod=factor();
	while(s[p]=='*'||s[p]=='/')
	{
		if(s[p]=='*')
		{
			p++;
			prod*=termen();
		}
		else
		{
			p++;
			prod/=termen();
		}
	}
	return prod;
}
int factor()
{
	int semn=1,val=0;
	while(s[p]=='-')
	{
		p++;
		semn=-semn;
	}
	if(s[p]=='(')
	{
		p++;
		val=expresie();
		p++;
		return semn*val;
	}
	while(s[p]>='0'&&s[p]<='9')
	{
		val=val*10+(s[p]-'0');
		p++;
	}
	return semn*val;
}
int main()
{
	in.open("evaluare.in",ios::in);
	out.open("evaluare.out",ios::out);
	in.get(s,100010);
	in.get();
	out<<expresie();
	in.close();
	out.close();
	return 0;
}