Submission

Status:

PPPPPPPPPP

Score: 100

User: admin

Problemset: J.Nine Khanaphat

Language: cpp

Time: 0.003 second

Submitted On: 2024-10-13 22:55:41

#include <bits/stdc++.h>
#define ll long long
using namespace std;

ll C[50];
ll count(ll x) {
//	printf("%lld\n", x);
	if (x < 9) return 0;
	if (x == 9) return 1;
	ll e = x;
	ll r = 0;
	while (e>0) {
		e/=10;r++;
	}
	ll div = x/C[r-1];
	ll mod = x%C[r-1];
	return div * (r-1)*C[r-2] + (div ==9 ? mod+1 : 0) + count(mod);
	
}
ll A, B;
int main() {
	C[0]=1;
	for (int i=1; i<=16; i++) C[i] = 10*C[i-1];
	scanf("%lld %lld", &A, &B);
	printf("%lld", count(B) - count(A-1));	
}