Submission #950044

#	Time	Username	Problem	Language	Result	Execution time	Memory
950044		vjudge1	Sjeckanje (COCI21_sjeckanje)	C++17	15 / 110	2017 ms	2544 KiB

Main

#pragma GCC optimize("Ofast,unroll-loops")
#pragma GCC target("avx,avx2,fma")
#include <bits/stdc++.h>
 
#define ff first
#define ss second
#define pb push_back
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define int long long
#define rnd(l, r) uniform_int_distribution<int>(l, r)(rng)
 
using namespace std;

void fp(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);} 
int pow(int a,int b,int m){int ans=1;while(b){if(b&1){ans=(ans*a)%m;}b>>=1;a=(a*a)%m;}return ans;}
int binpow(int a,int b){int ans=1;while(b){if(b&1){ans=(ans*a);}b>>=1;a=(a*a);}return ans;}
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
 
const int N = 2e5 + 10, MX = 2e5 + 10, inf = 1e18;

int a[N], dp[N], t[N * 4];

void update(int pos, int x, int v = 1,int tl = 0, int tr = MX){
    if(tl == tr){
        t[v] += x;
    }else{
        int mid = (tl + tr) >> 1;
        if(pos <= mid)
			update(pos, x, v * 2, tl, mid);
        else
			update(pos, x, v * 2 + 1,mid + 1, tr);
        t[v] = (t[v * 2] + t[v * 2 + 1]);
    }
}
 
int get(int l, int r, int v = 1, int tl = 0, int tr = MX){
    if(tl > r || tr < l)
        return 0;
    if(tl >= l && tr <= r){
        return t[v];
    }
    int mid = (tl + tr) >> 1;
    return (get(l, r, v * 2, tl, mid) + get(l, r, v * 2 + 1, mid + 1, tr));
}

main(){
	iostream::sync_with_stdio(false);	
    cin.tie(nullptr);
    cout.tie(nullptr);
	int n, q;
	cin >> n >> q;
	for(int i = 1; i <= n; i++){
		cin >> a[i];
	}
	while(q--){
		int l, r, x;
		cin >> l >> r >> x;
		for(int i = l; i <= r; i++){
			a[i] += x;
		}
		for(int i = 1; i <= n; i++){
			int mx = -inf, mn = inf;
			for(int j = i; j >= 1; j--){
				mx = max(a[j], mx);
				mn = min(mn, a[j]);
				dp[i] = max(dp[j - 1] + mx - mn, dp[i]);
			}
		}
		cout << dp[n] << endl;
		
		for(int i = 1; i <= n; i++){
			dp[i] = -inf;
		}
		//cout << endl;
	}
	//cout << ans << endl;
}	
/*
 * Before implementing the problem:
	
	Do I understand the problem correctly?
	Which places are tricky? What do I need to remember to implement them correctly?
	Which place is the heaviest by implementation? Can I do it simpler?
	Which place is the slowest? Where do I need to be careful about constant factors and where I can choose slower but simpler implementation?
	----------------------------------
	If not AC:
 
	Did you remember to do everything to handle the tricky places you thought about before?
	Is the solution correct?
	Do I understand the problem correctly?
	----------------------------------
	If you have a test on which the solution gives wrong answer:
 
	Is the solution doing what it was supposed to do?
	Is the problem in the code or in the idea?
*/

Compilation message (stderr)

Main.cpp:47:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   47 | main(){
      | ^~~~
Main.cpp: In function 'void fp(std::string)':
Main.cpp:15:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   15 | void fp(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:15:70: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   15 | void fp(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
      |                                                               ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 15 / 15
• Subtask 2: 0 / 40
• Subtask 3: 0 / 55