Submission #409474

# Submission time Handle Problem Language Result Execution time Memory
409474 2021-05-20T21:19:45 Z gmyu Feast (NOI19_feast) C++14
100 / 100
182 ms 10380 KB
/*
ID: USACO_template
LANG: C++
PROG: http://web.pdf.com/~pdfastest/fae/pdFT_Overview/pdft.html
*/
#include <iostream>  //cin , cout
#include <fstream>   //fin, fout
#include <stdio.h>   // scanf , pringf
#include <cstdio>
#include <algorithm> // sort , stuff
#include <stack>     // stacks
#include <queue>     // queues
#include <map>
#include <string>
#include <string.h>
#include <set>

using namespace std;

typedef pair<int, int>          pii;
typedef vector<int>             vi;     /// adjlist without weight
typedef vector<pii>             vii;    /// adjlist with weight
typedef vector<pair<int,pii>>   vpip;   /// edge with weight
typedef long long               ll;

#define mp  make_pair
#define ff  first
#define ss  second
#define pb  push_back
#define sz(x)   (int)(x).size()
#define adjread {int a, b; cin >> a >> b; adjlist[a].pb(b); adjlist[b].pb(a); }

const int MOD = 1e9+7;  // 998244353;
const int MX  = 2e5+5;   //
const ll  INF = 1e18;    //

#define MAXV 300007
#define MAXE 100007

const int xdir[4] = {1,0,-1,0}, ydir[4] = {0,1,0,-1}; /// 4 directions
struct NODE {
    int x, y;
    int val;
    int visited;
    bool operator< (NODE b) const { return (x == b.x) ? (y < b.y) : (x < b.x); }
};
struct EDGE {
    int from, to;
    ll weight;
    bool operator<(EDGE other) const { return weight < other.weight; }
};

bool debug;

int N, K;
ll ps[MAXV];

/**
 * dp[i] =  max (1 <=j <= j' <=i) { dp[j] + ps[i] - ps[j'] } = max { dp[j] - ps[j'] } + ps[i]
 * instead of doing O(N^2) DP, we use proximation
 * for each step, dp[i] = previous best { dp[j] - ps[j] } + ps[i] - err, where err is the proximation to optimal dp
 * and update previous best { } if dp[i]-ps[i] is better
*/
pair<ll, ll> dp[MAXV];
pair<ll, ll> canDo(ll err) {
    pair<ll, ll> bestDP = mp(0LL, 0LL);
    dp[0] = bestDP;
    for(int i=1; i<=N; i++) {
        dp[i] = mp(bestDP.ff + ps[i] - err, bestDP.ss + 1LL);
        dp[i] = max(dp[i], dp[i-1]);
        if(dp[i].ff - ps[i] > bestDP.ff) {
            bestDP = mp(dp[i].ff - ps[i], dp[i].ss);
        } else if(dp[i].ff - ps[i] == bestDP.ff && bestDP.ss > dp[i].ss) {
            bestDP = mp(dp[i].ff - ps[i], dp[i].ss);
        }
    }
    return dp[N];
}

int main() {
    debug = false;
    ios_base::sync_with_stdio(false); cin.tie(0);

    cin >> N >> K;
    for(int i = 1; i <=N; i++) {
        ll a; cin >> a;
        ps[i] = ps[i-1] + a;
    }

    ll lo = 0LL, hi = INF;
    while(lo < hi) {
        if(debug) cout << "walk " << lo << " " << hi << endl;
        ll mid = (lo + hi) / 2LL;
        auto ans = canDo(mid);
        if(ans.ss <= K) {
            hi = mid;
        } else {
            lo = mid + 1;
        }
    }

    auto ans = canDo(hi);
    cout << ans.ff + (ll)K * hi << endl;
}

/**
6 1
1 -2 3 -1 5 -6

6 2
1 2 3 -10 5 6

*/
# Verdict Execution time Memory Grader output
1 Correct 120 ms 9884 KB Output is correct
2 Correct 93 ms 9992 KB Output is correct
3 Correct 98 ms 10104 KB Output is correct
4 Correct 96 ms 10052 KB Output is correct
5 Correct 120 ms 10088 KB Output is correct
6 Correct 129 ms 9836 KB Output is correct
7 Correct 91 ms 9924 KB Output is correct
8 Correct 101 ms 10128 KB Output is correct
9 Correct 118 ms 9924 KB Output is correct
10 Correct 105 ms 9960 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 79 ms 8276 KB Output is correct
2 Correct 82 ms 8468 KB Output is correct
3 Correct 80 ms 8200 KB Output is correct
4 Correct 81 ms 8328 KB Output is correct
5 Correct 99 ms 9920 KB Output is correct
6 Correct 79 ms 8160 KB Output is correct
7 Correct 85 ms 8488 KB Output is correct
8 Correct 100 ms 10052 KB Output is correct
9 Correct 96 ms 9912 KB Output is correct
10 Correct 82 ms 8316 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 123 ms 10180 KB Output is correct
2 Correct 113 ms 10108 KB Output is correct
3 Correct 113 ms 10188 KB Output is correct
4 Correct 150 ms 10068 KB Output is correct
5 Correct 113 ms 10264 KB Output is correct
6 Correct 115 ms 10272 KB Output is correct
7 Correct 118 ms 10360 KB Output is correct
8 Correct 134 ms 10252 KB Output is correct
9 Correct 119 ms 10340 KB Output is correct
10 Correct 135 ms 10308 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 1 ms 204 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 1 ms 204 KB Output is correct
6 Correct 1 ms 204 KB Output is correct
7 Correct 1 ms 204 KB Output is correct
8 Correct 1 ms 204 KB Output is correct
9 Correct 1 ms 320 KB Output is correct
10 Correct 1 ms 332 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 1 ms 204 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 1 ms 204 KB Output is correct
6 Correct 1 ms 204 KB Output is correct
7 Correct 1 ms 204 KB Output is correct
8 Correct 1 ms 204 KB Output is correct
9 Correct 1 ms 320 KB Output is correct
10 Correct 1 ms 332 KB Output is correct
11 Correct 1 ms 332 KB Output is correct
12 Correct 1 ms 332 KB Output is correct
13 Correct 1 ms 332 KB Output is correct
14 Correct 1 ms 332 KB Output is correct
15 Correct 1 ms 332 KB Output is correct
16 Correct 1 ms 324 KB Output is correct
17 Correct 1 ms 332 KB Output is correct
18 Correct 1 ms 332 KB Output is correct
19 Correct 1 ms 332 KB Output is correct
20 Correct 1 ms 332 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 1 ms 204 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 1 ms 204 KB Output is correct
6 Correct 1 ms 204 KB Output is correct
7 Correct 1 ms 204 KB Output is correct
8 Correct 1 ms 204 KB Output is correct
9 Correct 1 ms 320 KB Output is correct
10 Correct 1 ms 332 KB Output is correct
11 Correct 1 ms 332 KB Output is correct
12 Correct 1 ms 332 KB Output is correct
13 Correct 1 ms 332 KB Output is correct
14 Correct 1 ms 332 KB Output is correct
15 Correct 1 ms 332 KB Output is correct
16 Correct 1 ms 324 KB Output is correct
17 Correct 1 ms 332 KB Output is correct
18 Correct 1 ms 332 KB Output is correct
19 Correct 1 ms 332 KB Output is correct
20 Correct 1 ms 332 KB Output is correct
21 Correct 2 ms 332 KB Output is correct
22 Correct 3 ms 332 KB Output is correct
23 Correct 3 ms 332 KB Output is correct
24 Correct 2 ms 332 KB Output is correct
25 Correct 2 ms 332 KB Output is correct
26 Correct 2 ms 332 KB Output is correct
27 Correct 2 ms 332 KB Output is correct
28 Correct 2 ms 332 KB Output is correct
29 Correct 2 ms 332 KB Output is correct
30 Correct 2 ms 332 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 120 ms 9884 KB Output is correct
2 Correct 93 ms 9992 KB Output is correct
3 Correct 98 ms 10104 KB Output is correct
4 Correct 96 ms 10052 KB Output is correct
5 Correct 120 ms 10088 KB Output is correct
6 Correct 129 ms 9836 KB Output is correct
7 Correct 91 ms 9924 KB Output is correct
8 Correct 101 ms 10128 KB Output is correct
9 Correct 118 ms 9924 KB Output is correct
10 Correct 105 ms 9960 KB Output is correct
11 Correct 79 ms 8276 KB Output is correct
12 Correct 82 ms 8468 KB Output is correct
13 Correct 80 ms 8200 KB Output is correct
14 Correct 81 ms 8328 KB Output is correct
15 Correct 99 ms 9920 KB Output is correct
16 Correct 79 ms 8160 KB Output is correct
17 Correct 85 ms 8488 KB Output is correct
18 Correct 100 ms 10052 KB Output is correct
19 Correct 96 ms 9912 KB Output is correct
20 Correct 82 ms 8316 KB Output is correct
21 Correct 123 ms 10180 KB Output is correct
22 Correct 113 ms 10108 KB Output is correct
23 Correct 113 ms 10188 KB Output is correct
24 Correct 150 ms 10068 KB Output is correct
25 Correct 113 ms 10264 KB Output is correct
26 Correct 115 ms 10272 KB Output is correct
27 Correct 118 ms 10360 KB Output is correct
28 Correct 134 ms 10252 KB Output is correct
29 Correct 119 ms 10340 KB Output is correct
30 Correct 135 ms 10308 KB Output is correct
31 Correct 1 ms 332 KB Output is correct
32 Correct 1 ms 204 KB Output is correct
33 Correct 1 ms 204 KB Output is correct
34 Correct 1 ms 204 KB Output is correct
35 Correct 1 ms 204 KB Output is correct
36 Correct 1 ms 204 KB Output is correct
37 Correct 1 ms 204 KB Output is correct
38 Correct 1 ms 204 KB Output is correct
39 Correct 1 ms 320 KB Output is correct
40 Correct 1 ms 332 KB Output is correct
41 Correct 1 ms 332 KB Output is correct
42 Correct 1 ms 332 KB Output is correct
43 Correct 1 ms 332 KB Output is correct
44 Correct 1 ms 332 KB Output is correct
45 Correct 1 ms 332 KB Output is correct
46 Correct 1 ms 324 KB Output is correct
47 Correct 1 ms 332 KB Output is correct
48 Correct 1 ms 332 KB Output is correct
49 Correct 1 ms 332 KB Output is correct
50 Correct 1 ms 332 KB Output is correct
51 Correct 2 ms 332 KB Output is correct
52 Correct 3 ms 332 KB Output is correct
53 Correct 3 ms 332 KB Output is correct
54 Correct 2 ms 332 KB Output is correct
55 Correct 2 ms 332 KB Output is correct
56 Correct 2 ms 332 KB Output is correct
57 Correct 2 ms 332 KB Output is correct
58 Correct 2 ms 332 KB Output is correct
59 Correct 2 ms 332 KB Output is correct
60 Correct 2 ms 332 KB Output is correct
61 Correct 157 ms 10200 KB Output is correct
62 Correct 182 ms 10316 KB Output is correct
63 Correct 134 ms 10128 KB Output is correct
64 Correct 165 ms 10308 KB Output is correct
65 Correct 165 ms 10308 KB Output is correct
66 Correct 168 ms 10380 KB Output is correct
67 Correct 161 ms 10040 KB Output is correct
68 Correct 117 ms 10336 KB Output is correct
69 Correct 126 ms 10140 KB Output is correct
70 Correct 113 ms 10004 KB Output is correct