Submission #602819

#	Time	Username	Problem	Language	Result	Execution time	Memory
602819		IvanJ	Growing Vegetables is Fun 4 (JOI21_ho_t1)	C++17	100 / 100	38 ms	9264 KiB

Main

#include<bits/stdc++.h>

using namespace std;

typedef long long ll;

const int maxn = 2e5 + 5;

int n;
int A[maxn];
int B[maxn];
int C[maxn];
int M1[maxn], M2[maxn];
ll pref[maxn];
ll suff[maxn];

int main() {
	scanf("%d", &n);
	for(int i = 0;i < n;i++) 
		scanf("%d", A + i);
	
	B[0] = 0;
	int maxi = A[0] + 1;
	for(int i = 1;i < n;i++) 
		B[i] = max(maxi - A[i], 0), maxi = max(maxi, A[i]) + 1, M1[i] = maxi;
	for(int i = 1;i < n;i++) 
		pref[i] = pref[i - 1] + (ll)max(B[i] - B[i - 1], 0);
	
	C[n - 1] = 0;
	maxi = A[n - 1] + 1;
	for(int i = n - 2;i >= 0;i--) 
		C[i] = max(maxi - A[i], 0), maxi = max(maxi, A[i]) + 1, M2[i] = maxi;
	for(int i = n - 2;i >= 0;i--) 
		suff[i] = suff[i + 1] + (ll)max(C[i] - C[i + 1], 0);
	
	ll ans = min(pref[n - 1], suff[0]);
	for(int i = 0;i < n - 1;i++) 
		ans = min(ans, max(pref[i], suff[i + 1]) + (M1[i] == M2[i + 1]));
	printf("%lld\n", ans);
	return 0;
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:18:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   18 |  scanf("%d", &n);
      |  ~~~~~^~~~~~~~~~
Main.cpp:20:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   20 |   scanf("%d", A + i);
      |   ~~~~~^~~~~~~~~~~~~

• Subtask 1: 40 / 40
• Subtask 2: 60 / 60