제출 #486122

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
486122		Duy_e	Rabbit Carrot (LMIO19_triusis)	C++14	0 / 100	1 ms	332 KiB

triusis

#include <bits/stdc++.h>
#define ll long long
#define ull unsigned long long
#define pii pair<long long, long long>
#define st first
#define nd second
#define file "test"
using namespace std;
const long long oo = 1e18;
const long long N = 2e5 + 5;

ll n, m, h[N], dp[N], best[N];

int main()
{
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    // #ifndef ONLINE_JUDGE
    //     freopen(file".inp","r",stdin); freopen(file".out","w",stdout);
    // #endif
    
    cin >> n >> m;
    for (int i = 1; i <= n; i ++)
        cin >> h[i];

    for (int i = 0; i <= n + 1; i ++)
        dp[i] = oo, best[i] = i - 1;

    dp[0] = 0;
    for (int i = 1; i <= n + 1; i ++){
        // for (int j = i + 1; j <= n + 1; j ++)
        //     if (h[i] - i*m >= h[j] - j*m)
        //         dp[j] = min(dp[j], dp[i] + j - i - 1);
        // // cout << dp[i] << ' ';

        for (int j = i - 1; j >= 0; j = best[j])
            if (h[j] + (i - j)*m >= h[i]) {
                ll cur = dp[j] + i - j - 1;
                if (cur < dp[i]) dp[i] = cur, best[i] = j;
            }
    }


    cout << dp[n + 1];
    

    return 0;
}    
/**  /\_/\
    (= ._.)
    / >0  \>1 
  ________________________
 / Brainstorming section /
/=======================/
---
===
with two fixed point i, j you are allowed to change every pole between i, j
-> could it be changed so that you can go from i->j
possible case: 
+ a[j] <= a[i]
+ h[i] + (j - i)*m >= h[j]

===
**/
// Before submit: spot the visible bug by reading the code. 

• Subtask 1: 0 / 14
• Subtask 2: 0 / 21
• Subtask 3: 0 / 28
• Subtask 4: 0 / 37