Submission #497981

#	Time	Username	Problem	Language	Result	Execution time	Memory
497981		armashka	Gift (IZhO18_nicegift)	C++17	100 / 100	629 ms	111580 KiB

nicegift

#include <bits/stdc++.h>
 
//#pragma comment(linker, "/stack:200000000")
//#pragma GCC optimize("Ofast")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
 
#define fast ios_base::sync_with_stdio(false);cin.tie(nullptr);cout.tie(nullptr);
#define all(v) v.begin(),v.end()
#define pb push_back
#define sz size()
#define ft first
#define sd second
 
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pll;
typedef unsigned long long ull;
 
const int N = 1e6 + 5;
const ll M = 1e8;
const ll inf = 1e18;
const ll mod = 1e9;
const double Pi = acos(-1); 
 
ll binpow(ll x, ll ti) { ll res = 1;while (ti){if(ti & 1)res *= x;x *= x;ti >>= 1; x %= mod; res %= mod;} return res;}
ll binmul(ll x, ll ti) { ll res = 0;while (ti){if(ti & 1)res += x;x += x;ti >>= 1; x %= mod; res %= mod;} return res;}
ll nok(ll a, ll b) { return (a*b)/__gcd(abs(a),abs(b)) * (a*b > 0 ? 1 : -1); }
bool odd(ll n) { return (n % 2 == 1); }
bool even(ll n) { return (n % 2 == 0); }            

ll n, k, sum, l[N], mx, cnt;
pll a[N], b[N];
vector <pll> q[N]; 

const void solve(/*Armashka*/) {
	cin >> n >> k;
	for (int i = 1; i <= n; ++ i) cin >> a[i].ft, a[i].sd = i;
	sort(a + 1, a + n + 1);
	for (int i = 1; i <= n; ++ i) b[i] = a[i], sum += a[i].ft, mx = max(mx, a[i].ft);
	if (sum % k || mx > sum / k) {
		cout << "-1\n";
		return;
	}			
	ll s = 0, cur = 1;
	for (int i = 1; i <= n; ++ i) {
		if (s + a[i].ft <= sum / k) {
			q[cur].pb({a[i].ft, a[i].sd});
			s += a[i].ft;
			if (s == sum / k) {
				s = 0;
				++ cur;
			}			
		} else {
			q[cur].pb({(sum / k) - s, a[i].sd});
			++ cur;
			s = a[i].ft - ((sum / k) - s);
			q[cur].pb({s, a[i].sd});			
		}
	}
	while (1) {
		multiset <pll> st;
		for (int i = 1; i <= k; ++ i) {
			if (l[i] < q[i].sz) st.insert({q[i][l[i]].ft, i});
		}
		if (st.empty()) break;
		for (auto [x, pos] : st) {
			if (x == st.begin()->ft) q[pos][l[pos]].ft = 0, ++ l[pos];
			else q[pos][l[pos]].ft -= st.begin()->ft;
		}
		++ cnt;
	}
	cout << cnt << "\n";
	for (int i = 1; i <= k; ++ i) q[i].clear();
	s = 0, cur = 1;
	for (int i = 1; i <= n; ++ i) {
		if (s + a[i].ft <= sum / k) {
			q[cur].pb({a[i].ft, a[i].sd});
			s += a[i].ft;
			if (s == sum / k) {
				s = 0;
				++ cur;
			}			
		} else {
			q[cur].pb({(sum / k) - s, a[i].sd});
			++ cur;
			s = a[i].ft - ((sum / k) - s);
			q[cur].pb({s, a[i].sd});			
		}
	}
	for (int i = 1; i <= k; ++ i) l[i] = 0;
	while (1) {
		multiset <pair<pll, ll>> st;
		for (int i = 1; i <= k; ++ i) {
			if (l[i] < q[i].sz) st.insert({q[i][l[i]], i});
		}
		if (st.empty()) break;
		cout << st.begin()->ft.ft << " ";
		for (auto [x, pos] : st) {
			if (x.ft == st.begin()->ft.ft) q[pos][l[pos]].ft = 0, ++ l[pos];
			else q[pos][l[pos]].ft -= st.begin()->ft.ft;
			cout << x.sd << " ";
		}
		cout << "\n";
	}	
}
            
signed main() {
    fast;
    //freopen("divide.in", "r", stdin);
    //freopen("divide.out", "w", stdout);
    int tt = 1;
    //cin >> tt;
    while (tt --) {                                                
        solve();
    }
}
 
/*
5 4 4
1 2
3 1
3 4
5 3
4 5 2 3
2 1 3 1
1 3 5
2 3 4 5
2 1 3 1
*/

Compilation message (stderr)

nicegift.cpp: In function 'const void solve()':
nicegift.cpp:63:13: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   63 |    if (l[i] < q[i].sz) st.insert({q[i][l[i]].ft, i});
      |             ^
nicegift.cpp:94:13: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   94 |    if (l[i] < q[i].sz) st.insert({q[i][l[i]], i});
      |             ^

• Subtask 1: 7 / 7
• Subtask 2: 11 / 11
• Subtask 3: 12 / 12
• Subtask 4: 19 / 19
• Subtask 5: 51 / 51