Submission #482921

#	Time	Username	Problem	Language	Result	Execution time	Memory
482921		MilosMilutinovic	Distributing Candies (IOI21_candies)	C++17	11 / 100	160 ms	29136 KiB

candies

#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define pb push_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
typedef vector<int> VI;
typedef long long ll;
typedef pair<int,int> PII;
typedef double db;
mt19937 mrand(random_device{}());
const ll mod=1000000007;
int rnd(int x) { return mrand() % x;}
ll powmod(ll a,ll b) {ll res=1;a%=mod; assert(b>=0); for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;}
ll gcd(ll a,ll b) { return b?gcd(b,a%b):a;}
// head

const int N=201000;
int n,q;
VI qs2[N];
ll pref4[N],mn[N],mx[N];
VI distribute_candies(VI c,VI l,VI r,VI v) {
	n=SZ(c),q=SZ(v);
	VI a(n);
	if (n<=2000&&q<=2000) {
		rep(i,0,q) rep(j,l[i],r[i]+1) a[j]+=v[i],a[j]=max(a[j],0),a[j]=min(a[j],c[j]);
		return a;
	}
	bool sb2=true;
	rep(i,0,q) if (v[i]<0) sb2=false;
	if (sb2) {
		rep(i,0,q) {
			qs2[l[i]].pb(v[i]);
			qs2[r[i]+1].pb(-v[i]);
		}
		ll tot=0;
		rep(i,0,n) {
			for (auto x:qs2[i]) tot+=x;
			a[i]=min((ll)c[i],tot);
		}
		return a;
	}
	bool sb4=true;
	rep(i,0,q) if (l[i]!=0||r[i]!=n-1) sb4=false;
	if (sb4) {
		pref4[0]=v[0];
		rep(i,1,q) pref4[i]=pref4[i-1]+v[i];
		mx[q-1]=mn[q-1]=pref4[q-1];
		per(i,0,q-1) mx[i]=max(pref4[i],mx[i+1]),mn[i]=min(pref4[i],mn[i+1]);
		rep(i,0,n) {
			if (mx[0]-mn[0]<=c[i]) a[i]=pref4[q-1]-mn[0];
			else {
				int l=0,r=q-1,pos=0;
				while (l<=r) {
					int md=(l+r)>>1;
					if (mx[md]-mn[md]>c[i]) pos=md,l=md+1;
					else r=md-1;
				}
				if (pref4[pos]<pref4[q-1]) a[i]=c[i]-(mx[pos]-pref4[q-1]);
				else a[i]=pref4[q-1]-mn[pos];
			}
		}
	}
}

Compilation message (stderr)

candies.cpp: In function 'VI distribute_candies(VI, VI, VI, VI)':
candies.cpp:68:1: warning: control reaches end of non-void function [-Wreturn-type]
   68 | }
      | ^

• Subtask 1: 3 / 3
• Subtask 2: 8 / 8
• Subtask 3: 0 / 27
• Subtask 4: 0 / 29
• Subtask 5: 0 / 33