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#include <fstream>
using namespace std;
fstream fin("evaluare.in"),fout("evaluare.out");
string s;
int p=0;
int expr();
int termen();
int factor();
int sum;
int expr()
{
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*=factor();
}
else
{
p++;
prod/=factor();
}
return prod;
}
int factor()
{
int semn=1,val=0;
while(s[p]=='-')
{
p++;
semn=-semn;
}
if(s[p]=='(')
{
p++;
val=expr();
p++;
return semn*val;
}
while(s[p]>='0' && s[p]<='9')
{
val=val*10+s[p]-'0';
p++;
}
return semn*val;
}
int main()
{
fin>>s;
fout<<expr();
return 0;
}