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#include <fstream>
#include <cstring>
#include <stack>
#define plus 1000000001
#define minus 1000000002
#define im 1000000003
#define imp 1000000004
using namespace std;
ifstream fin("evaluare.in");
ofstream fout("evaluare.out");
char s[100001];
int a[100001], n;
inline int P(char c)
{
if(c=='+'||c=='-') return 1;
return 2;
}
void Poloneza()
{
stack <char> ST;
int i, nr;
char c;
for(i=0; s[i]!=0; i++)
{
if(s[i]=='(') ST.push(s[i]);
if(s[i]>='0'&&s[i]<='9')
{
nr=0;
while(s[i]>='0'&&s[i]<='9')
{
nr=nr*10+s[i]-'0';
i++;
}
i--;
a[n++]=nr;
}
if(s[i]==')')
{
while(ST.top()!='(')
{
c=ST.top();
if(c=='+') a[n++]=plus;
if(c=='-') a[n++]=minus;
if(c=='*') a[n++]=im;
if(c=='/') a[n++]=imp;
ST.pop();
}
ST.pop();
}
if(strchr("+-*/", s[i])!=NULL)
{
if(ST.empty()) ST.push(s[i]);
else if(ST.top()=='(') ST.push(s[i]);
else
{
while(!ST.empty()&&P(ST.top())>=P(s[i]))
{
c=ST.top();
if(c=='+') a[n++]=plus;
if(c=='-') a[n++]=minus;
if(c=='*') a[n++]=im;
if(c=='/') a[n++]=imp;
ST.pop();
}
ST.push(s[i]);
}
}
}
while(!ST.empty())
{
c=ST.top();
if(c=='+') a[n++]=plus;
if(c=='-') a[n++]=minus;
if(c=='*') a[n++]=im;
if(c=='/') a[n++]=imp;
ST.pop();
}
}
void Evaluare()
{
stack <int> ST;
int i, x, y, v;
for(i=0; i<n; i++)
if(a[i]<plus) ST.push(a[i]);
else
{
x=ST.top(); ST.pop();
y=ST.top(); ST.pop();
if(a[i]==plus) v=x+y;
if(a[i]==minus) v=y-x;
if(a[i]==im) v=x*y;
if(a[i]==imp)
if(x!=0) v=y/x;
else v=0;
ST.push(v);
}
fout<<ST.top();
}
int main()
{
fin>>s;
Poloneza();
Evaluare();
fin.close();
fout.close();
return 0;
}