#include <stdio.h>
 
#define SIZE 10
double stack[SIZE];
int sp;
 
void pushu(double value);
double pop(void);
int isFull(void);
int isEmpty(void);
void reset(void);
 
int main(void) {
	reset();
 
	while(1){
		double data;
		double cal1,cal2;
		int resp;
 
		scanf("%d",&resp);
 
		if(resp==9) break;
 
		switch(resp){
			case 1: cal1 = pop();
				cal2 = pop();
				pushu(cal2+cal1);
				break;
 
			case 2: cal1 = pop();
				cal2 = pop();
				pushu(cal2-cal1);
				break;
 
			case 3: cal1 = pop();
				cal2 = pop();
				pushu(cal2*cal1);
				break;
 
			case 4: cal1 = pop();
				cal2 = pop();
				pushu(cal2/cal1);
				break;
 
			case 5: printf("data"); scanf("%lf",&data);
				pushu(data);
				printf("%lf\n",data);
				break;
	}
}
		answer();
		return 0;
}
 
void pushu(double value){
	if(isFull()){
		printf("スタックが満杯で入りませんでした\n");
	}else{
		stack[sp++] = value;
	}
}
 
double pop(void){
	if(isEmpty()){
		printf("スタックが空で取り出せませんでした\n");
		return 0;
	}else{
		return stack[--sp];
	}
}
 
int isFull(void){
		if(sp>=SIZE){
			return 1;
		}else{
			return 0;
		}
	}
 
int isEmpty(void){
		if(sp<=0){
			return 1;
		}else{
			return 0;
		}
}
 
void answer(void){
	printf("\n");
	printf("answer:%lf\n",stack[0]);
}
void reset(void){
	while(!isEmpty())
	pop();
}

I2luY2x1ZGUgPHN0ZGlvLmg+CgojZGVmaW5lIFNJWkUgMTAKZG91YmxlIHN0YWNrW1NJWkVdOwppbnQgc3A7Cgp2b2lkIHB1c2h1KGRvdWJsZSB2YWx1ZSk7CmRvdWJsZSBwb3Aodm9pZCk7CmludCBpc0Z1bGwodm9pZCk7CmludCBpc0VtcHR5KHZvaWQpOwp2b2lkIHJlc2V0KHZvaWQpOwoKaW50IG1haW4odm9pZCkgewoJcmVzZXQoKTsKCQoJd2hpbGUoMSl7CgkJZG91YmxlIGRhdGE7CgkJZG91YmxlIGNhbDEsY2FsMjsKCQlpbnQgcmVzcDsKCQkKCQlzY2FuZigiJWQiLCZyZXNwKTsKCQkKCQlpZihyZXNwPT05KSBicmVhazsKCQkKCQlzd2l0Y2gocmVzcCl7CgkJCWNhc2UgMTogY2FsMSA9IHBvcCgpOwoJCQkJY2FsMiA9IHBvcCgpOwoJCQkJcHVzaHUoY2FsMitjYWwxKTsKCQkJCWJyZWFrOwoJCQkJCgkJCWNhc2UgMjogY2FsMSA9IHBvcCgpOwoJCQkJY2FsMiA9IHBvcCgpOwoJCQkJcHVzaHUoY2FsMi1jYWwxKTsKCQkJCWJyZWFrOwoJCQkJCgkJCWNhc2UgMzogY2FsMSA9IHBvcCgpOwoJCQkJY2FsMiA9IHBvcCgpOwoJCQkJcHVzaHUoY2FsMipjYWwxKTsKCQkJCWJyZWFrOwoJCQkJCgkJCWNhc2UgNDogY2FsMSA9IHBvcCgpOwoJCQkJY2FsMiA9IHBvcCgpOwoJCQkJcHVzaHUoY2FsMi9jYWwxKTsKCQkJCWJyZWFrOwoJCQkKCQkJY2FzZSA1OiBwcmludGYoImRhdGEiKTsgc2NhbmYoIiVsZiIsJmRhdGEpOwoJCQkJcHVzaHUoZGF0YSk7CgkJCQlwcmludGYoIiVsZlxuIixkYXRhKTsKCQkJCWJyZWFrOwoJfQp9CgkJYW5zd2VyKCk7CgkJcmV0dXJuIDA7Cn0KCnZvaWQgcHVzaHUoZG91YmxlIHZhbHVlKXsKCWlmKGlzRnVsbCgpKXsKCQlwcmludGYoIuOCueOCv+ODg+OCr+OBjOa6gOadr+OBp+WFpeOCiuOBvuOBm+OCk+OBp+OBl+OBn1xuIik7Cgl9ZWxzZXsKCQlzdGFja1tzcCsrXSA9IHZhbHVlOwoJfQp9Cgpkb3VibGUgcG9wKHZvaWQpewoJaWYoaXNFbXB0eSgpKXsKCQlwcmludGYoIuOCueOCv+ODg+OCr+OBjOepuuOBp+WPluOCiuWHuuOBm+OBvuOBm+OCk+OBp+OBl+OBn1xuIik7CgkJcmV0dXJuIDA7Cgl9ZWxzZXsKCQlyZXR1cm4gc3RhY2tbLS1zcF07Cgl9Cn0KCmludCBpc0Z1bGwodm9pZCl7CgkJaWYoc3A+PVNJWkUpewoJCQlyZXR1cm4gMTsKCQl9ZWxzZXsKCQkJcmV0dXJuIDA7CgkJfQoJfQoJCmludCBpc0VtcHR5KHZvaWQpewoJCWlmKHNwPD0wKXsKCQkJcmV0dXJuIDE7CgkJfWVsc2V7CgkJCXJldHVybiAwOwoJCX0KfQoKdm9pZCBhbnN3ZXIodm9pZCl7CglwcmludGYoIlxuIik7CglwcmludGYoImFuc3dlcjolbGZcbiIsc3RhY2tbMF0pOwp9CnZvaWQgcmVzZXQodm9pZCl7Cgl3aGlsZSghaXNFbXB0eSgpKQoJcG9wKCk7Cn0=

NQoxCjUKMgoxCjk=

5
1
5
2
1
9