Submission #1119649

#	Time	Username	Problem	Language	Result	Execution time	Memory
1119649		InvMOD	K blocks (IZhO14_blocks)	C++14	0 / 100	3 ms	2128 KiB

blocks

#include <bits/stdc++.h>
using namespace std;

#define fi first
#define se second
#define gcd __gcd
#define sz(v) (int) v.size()
#define pb push_back
#define pi pair<int,int>
#define all(v) (v).begin(), (v).end()
#define compact(v) (v).erase(unique(all(v)), (v).end())
#define FOR(i, a, b) for(int i = (a); i <= (b); i++)
#define dbg(x) "[" #x " = " << (x) << "]"
///#define int long long

using ll = long long;
using ld = long double;
using ull = unsigned long long;

template<typename T> bool ckmx(T& a, const T& b){if(a < b) return a = b, true; return false;}
template<typename T> bool ckmn(T& a, const T& b){if(a > b) return a = b, true; return false;}

const int N = 1e5+5;
const ll MOD = 1e9+7;
const ll INF = 1e18;


int n, k, a[N];

namespace Subtask1{
    bool ckSub(){
        return n <= 1e2;
    }

    const int N = 105, K = 105;

    int dp[K][N];

    void process()
    {
        FOR(i, 0, k){
            FOR(j, 0, n){
                dp[i][j] = 1e9 + 1;
            }
        }

        dp[0][0] = 0;
        FOR(i, 1, k){
            FOR(r, 1, n){

                int Mx = a[r];
                for(int l = i; l >= 1; l--){
                    ckmx(Mx, a[l]);
                    ckmn(dp[i][r], dp[i-1][l-1] + Mx);
                }
            }
        }

        cout << dp[k][n] <<"\n";
        return;
    }
}

namespace Subtask2{
    bool ckSub(){
        return n <= N;
    }

    const int K = 105;

    ll dp[2][N];

    void compute(int l, int r, int optL, int optR){
        if(l > r) return;

        int mid = l+r>>1;

        int best = 0; ll last = INF, Mx = a[min(mid, optR)];
        for(int i = min(mid, optR); i >= optL; i--){
            ckmx(Mx, 1ll * a[i]);

            if(ckmn(last, dp[0][i-1] + Mx)){
                best = i;
            }
        }

        dp[1][mid] = last;
        compute(l, mid-1, optL, best);
        compute(mid+1, r, best, optR);
        return;
    }

    void process()
    {
        FOR(i, 0, 1){
            FOR(j, 0, n){
                dp[i][j] = INF;
            }
        }

        dp[0][0] = 0;
        FOR(i, 1, k){
            compute(1, n, 1, n);
            swap(dp[0], dp[1]);
            dp[0][0] = INF;
        }

        cout << dp[0][n] <<"\n";
        return;
    }
}

void solve()
{
    cin >> n >> k;
    FOR(i, 1, n) cin >> a[i];

    Subtask2::process(); return;
    if(Subtask1::ckSub()){
        return Subtask1::process(), void();
    }
    else{
        return Subtask2::process(), void();
    }
    return;
}

signed main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    #define name "InvMOD"
    if(fopen(name".INP", "r")){
        freopen(name".INP","r",stdin);
        freopen(name".OUT","w",stdout);
    }

    int t = 1; //cin >> t;
    while(t--) solve();
    return 0;
}

Compilation message (stderr)

blocks.cpp: In function 'void Subtask2::compute(int, int, int, int)':
blocks.cpp:76:20: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   76 |         int mid = l+r>>1;
      |                   ~^~
blocks.cpp: In function 'int main()':
blocks.cpp:136:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  136 |         freopen(name".INP","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
blocks.cpp:137:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  137 |         freopen(name".OUT","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 14
• Subtask 2: 0 / 18
• Subtask 3: 0 / 21
• Subtask 4: 0 / 47