#include<stdio.h>
#include<ctype.h>
#include<string.h>
#define max 100
char s[max];
int top=-1;
void push(char c){
    s[++top]=c;
}
char pop(){
    return s[top--];
}
int pre(char c){
    if(c=='+' || c=='-')
    return 1;
    if(c=='*' || c=='/')
    return 2;
   return 0;
}
char peek(){
    return s[top];
}
int isoperator(char c){
    return (c=='+'||c=='-'||c=='*'||c=='/');
}
int main(){
    char in[100],postfix[100];
    int k=0,valid=1;
    int balance=0;
    scanf("%s",in);
    for(int i=0;in[i]!='\0';i++){
        char ch=in[i];
        if(isalnum(ch)){
            post[k++]=ch;
        }
        else if(ch=='('){
            push(ch);
        }
        else if(ch==')'){
            while(top!=-1 && peek()!='('){
               postfix[k++]=pop();
            }
            if(top==-1){
                valid=0;
                break;
            }
            pop();
        }
         else if(isOperator(ch)){
             while(top!=1&&pre(peek())>=pre(ch)){
                 postfix[k++]=pop();
             }
             push(ch);
         }
         else{
             valid=0;
             break;
         }
    }
    while(top!=-1){
        if(peek()=='('){
            valid=0;
            break;
            
        }
            postfix[k++]=pop();
        }
        postfix[k]='\0';
        if(!valid){
            printf("%s",postfix);
        }
        return 0;
    }