C :

#include<stdio.h>   

int main(){ 
	int i,n,c=0;
	scanf("%d",&n);

	
	for(i = 5;i <= n;i++){
		int w = i / 10000;
		int q = i / 1000 % 10;
		int b = i / 100 % 10;
		int s = i / 10 % 10;
		int g = i % 10;
		
		if((w == 5 || q == 5 || b == 5 || s == 5 || g == 5) && i % 5 == 0){
		
			c++;
		}
	}
	
	printf("%d",c);
	return 0;
} 

C++ :

#include<iostream>
#include<math.h>
using namespace std;
int main(){
    int n,i,a,b,c,d,e,f = 0;
    cin>>n;
    i = 1;
    while(i <= n){ 
  a = i / 10000;
  b = i / 1000 % 10;
  c = i / 100 % 10;
  d = i / 10 % 10;
  e = i % 10;
  if((i % 5 == 0) && (a == 5 || b == 5 || c == 5 || d == 5 || e == 5) ){
      f++;
  }
  i++;
}
cout<<f<<endl;
return 0;
}