Submission

Status:

PPPPPPPPPP

Score: 100

User: Dormon

Problemset: J.Nine Khanaphat

Language: cpp

Time: 0.002 second

Submitted On: 2024-12-03 10:41:57

#include <iostream>

using namespace std;
using ll = long long;

ll calc(ll n) {
    ll ans = 0ll;
    for (ll i = 1;i <= n;i *= 10){
        ll suf = n/(i*10), curr = (n/i)%10, pre = n%i;

        if (curr < 9) ans += suf*i;
        else if (curr == 9) ans += suf*i+pre+1;
        else ans += (curr+1)*i;
    }
    return ans;
}

int main() {
    ll a, b; scanf("%lld %lld", &a, &b);
    printf("%lld", calc(b)-calc(a-1));

    return 0;
}