#include <stdio.h> int sum,count=0; int count1(int n) { sum=0; while(n>0) { sum=sum+n%10; n=n/10; } if(sum%5==0) { count++; } return count; } int main() { int a,b,i=0; scanf("%d %d",&a,&b); for(i=a;i<=b;i++) { count1(i); } printf("%d",count); return 0; }