#include<stdio.h>
#include<stdlib.h>

typedef struct rectangle{
    float length;
    float width;
    struct rectangle *next;
}rect;

rect *head = NULL,*tail;



void area(float *l,float *w,int *ar){
    *ar = l * w;
}

int main(){
    float l,w;
    int ar=0;
    
    scanf("%.1f",&l);
    scanf("%1.f".&w);
    if(l<0 || w<0){
        printf("Invalid input");
    }
    area(&l,&w,&ar);
    printf("%.2f",ar)
}