Submission #93511

#	Time	Username	Problem	Language	Result	Execution time	Memory
93511		Pancake	Stove (JOI18_stove)	C++14	100 / 100	36 ms	6376 KiB

stove

#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,sse3,sse4,popcnt,abm,mmx")

#include <bits/stdc++.h>	
#include <stdio.h>    
 
using namespace std;
     
#define F first
#define S second
#define lb lower_bound          	    
#define ub upper_bound
#define pb push_back
#define pf push_front    
#define ppb pop_back
#define mp make_pair
#define bpp __builtin_popcount                                                                                        
#define sqr(x) ((x) * (x))
#define al 0x3F3F3F3F
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define in insert
#define ppf pop_front
#define endl '\n'
#define int long long
 
typedef unsigned long long ull;
typedef long long ll;
typedef long double ld;
typedef pair <int, int> pii;
 
const int mod = (int)1e9 + 7;                                  
const int N = (int)2e5 + 123;
const ll inf = (ll)3e18 + 1;
                                       
const double pi = acos(-1.0);
const double eps = 1e-7;
const int dx[] = {0, 0, 1, 0, -1};							
const int dy[] = {0, 1, 0, -1, 0};  		
 
int n, k, ans, a[N], res[N], p[N], sz[N], e;

int get (int v) {
	if (v == p[v]) return v;
	return p[v] = get (p[v]);
}

inline void unite (int x, int y, int cost) {
	int u = get (x), v = get (y);
	if (u == v) return;
	if (sz[u] < sz[v]) swap (u, v);
	sz[u] += sz[v];
	p[v] = u;
	e --;
	ans += cost;
}

inline void boost () {
	ios_base :: sync_with_stdio (NULL);
	cin.tie (NULL), cout.tie (NULL);          
}

inline void Solve () {
	cin >> n >> k;
	e = n;
	for (int i = 1; i <= n; i ++) cin >> a[i];
	vector < pair <int, pii> > v;
	for (int i = 1; i <= n; i ++) p[i] = i, sz[i] = 1;
	for (int i = 1; i < n; i ++) v.pb ({a[i + 1] - a[i], {i, i + 1} });
	sort (all (v));
	for (auto it : v) {
		if (e == k) break;
		int cost = it.F, x = it.S.F, y = it.S.S;
		unite (x, y, cost);
	}
	cout << ans + k;
}
                  
main () {                                       
//	freopen (".in", "r", stdin);    
//	freopen (".out", "w", stdout); 	          
	boost ();
	int tt = 1;
//	cin >> tt;   
	while (tt --) {
		Solve ();
	}                                               
	return 0;      
}         	                                                    

Compilation message (stderr)

stove.cpp:79:7: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main () {                                       
       ^

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