#include<stdio.h>

int main()
{
int t;
scanf("%d",&t);
int m=t/10;
int n=t%10;

switch(n){
case 1:
	printf("Faint signals, barely perceptible");
	break;
case 2:
	printf("Very weak signals");
	break;
case 3:
	printf("Weak signals");
    break;
case 4:
	printf("Fair signals");
	break;
case 5:
	printf("Fairly good signals");
	break;
case 6:
	printf("Good signals");
	break;
case 7:
	printf("Moderately strong signals");
	break;
case 8:
	printf("Strong signals");
	break;
case 9:
	printf("Extremely strong signals");
	break;
}
switch(m){
case 1:
	printf(", unreadable.");
	break;
case 2:
    printf(", barely readable, occasional words distinguishable.");
    break;
case 3:
    printf(", readable with considerable difficulty.");
    break;
case 4:
    printf(", readable with practically no difficulty.");
    break;
case 5:
    printf(", perfectly readable.");
    break;
}

}