Submission #831301

#	Time	Username	Problem	Language	Result	Execution time	Memory
831301		manhtuan22007	Stove (JOI18_stove)	C++14	0 / 100	1 ms	212 KiB

stove

#include <bits/stdc++.h>
//#define int long long
#define ll long long
using namespace std;

const int maxn = 1e5 + 10;

int n , k , a[maxn];

int cal(int x){
	int j = 1 , cnt = 1;
	for(int i = 1 ; i <= n ; i ++){
		if(a[i] - a[j] + 1 <= x) continue;
		j = i;
		++cnt; 
	}
	return cnt;
}

int32_t main()
{
	cin.tie(0)->sync_with_stdio(0);
	if(fopen(".inp" , "r")){
		freopen(".inp" , "r" , stdin);
		freopen(".out" , "w" , stdout);
	}
	cin >> n >> k;
	for(int i = 1 ; i <= n ; i ++) cin >> a[i];
	int l = 0 , r = 1e9 + 1 , ans = 1e9;
	// cout << cal(3) << "\n";
	while(l <= r){
		int mid = (l + r) / 2;
		if(cal(mid) <= k) ans = mid , r = mid - 1;
		else l = mid + 1;
	}
	// cout << ans << " ";
	ll res = 0 , j = 0;
	for(int i = 1 ; i <= n ; i = j + 1){
		while(a[j + 1] - a[i] + 1 <= ans && j < n){
			++j;
		}
		res += a[j] - a[i] + 1;
		// cout << i << " " << j << '\n';
	}
	
	cout << res;
}	

Compilation message (stderr)

stove.cpp: In function 'int32_t main()':
stove.cpp:24:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   24 |   freopen(".inp" , "r" , stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
stove.cpp:25:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   25 |   freopen(".out" , "w" , stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 20
• Subtask 2: 0 / 30
• Subtask 3: 0 / 50