Submission #217383

#	Time	Username	Problem	Language	Result	Execution time	Memory
217383		bayemirov	Trol (COCI19_trol)	C++17	50 / 50	5 ms	384 KiB

trol

//bayemirov                                       
#include <bits/stdc++.h>               

using namespace std;

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

typedef long long ll;

#define pb push_back

ll g(ll x) {
	return x * (x + 1) / 2;
}

ll sumofDigits(ll x, ll res = 0) {
	while (x) {
		res += x % 10;
		x /= 10;
	}
	return res;
}

ll get(ll x) {
	while (x >= 10) 
		x = sumofDigits(x);
	return x;
}

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);
	int q;
	cin >> q;
	while (q--) {
		ll l, r;
		cin >> l >> r;
		ll ans = 0;
		ll pref = get(l);
		ll suff = get(r);
		ll k = r/9 - (l-1)/9;
		if (pref > 1) k--;
		if (k == 0) {
			while (l <= r) { 
				ans += get(l);
				l++;
			}
			cout << ans << "\n";
			continue;
		}
		ans = k * 45;
		while (pref > 1ll && pref < 10ll)
			ans += pref++;
		if (suff < 9)
			ans += g(suff);
	  	cout << ans << "\n";
	}
	return 0;
}                    

• Subtask 1: 50 / 50