#include<stdio.h>
#include<assert.h>
#include<math.h>
#include<string.h>

int stack[100];
int top = 0;

void push(int v){
    stack[top++] = v;
}

int pop(){
    return stack[--top];
}

int getInt(char *s){
    int i
    int ret=0;
    int size = strlen(s);
    
    for(i=0;i<size;i++){
        ret += (s[i]-'0')*pow(10,size-i-1);
    }
    return ret;
}

int main(){
    
    char s[1000];
    while(scanf("%s",s)!=EOF){
      if('0' <= s[0] && s[0] <= '9'){
          int v = getInt(s);
          push(v);
          continue;
          
      }
      
	  int a,b;
	  b = pop();
	  a = pop();
	  
	  if(s[0] == '+'){
	      push(a+b);
	  }
	  else if(s[0] == '-'){
	      push(a-b);
	  }
	  else if(s[0] == '*'){
	      push(a*b);
	  }
	  else{
	      assert(0);
	  }
	  
	  printf("%d\n",pop());
	  return 0;
}

