Submission #555850

#	Time	Username	Problem	Language	Result	Execution time	Memory
555850		urosk	K blocks (IZhO14_blocks)	C++14	0 / 100	1 ms	340 KiB

blocks

// __builtin_popcount(x)
// __builtin_popcountll(x)
#define here cerr<<"===========================================\n"
#include <bits/stdc++.h>
#define ld double
#define ll long long
#define ull unsigned long long
#define llinf 100000000000000000LL // 10^17
#define iinf 2000000000 // 2*10^9
#define pb push_back
#define popb pop_back
#define fi first
#define sc second
#define endl '\n'
#define pii pair<int,int>
#define pll pair<ll,ll>
#define pld pair<ld,ld>
#define sz(a) int(a.size())
#define all(a) a.begin(),a.end()
#define ceri(a,l,r) {for(ll i_ = l;i_<=r;i_++) cerr<<a[i_]<< " ";cerr<<endl;}
using namespace std;

#define maxn 100005
#define maxk 105
#define lg 25
ll n,k;
ll a[maxn];
bool pisi = 1;
ll st[maxn][lg];
ll powi[maxn];
bool test = 0;
ll get(ll l,ll r){
    ll len = (r-l+1);
    ll k = powi[len];
    ll ans = min(st[l][k],st[r-(1<<k)+1][k]);
    if(0){
        ll g =0 ;
        for(ll i = l;i<=r;i++) g = max(g,a[i]);
        if(g!=ans){
            cerr<<"MIN: "<<l<< " "<<r<<endl;
            exit(0);
        }
    }
    return ans;
}

ll brut(){
    vector<vector<ll> > v(n+1,vector<ll>(k+1,0));
    v[0][0] = 0;
    for(ll i = 1;i<=n;i++) v[i][0] = llinf;
    for(ll j = 1;j<=k;j++){
        v[0][j] = llinf;
        for(ll i = 1;i<=n;i++){
            v[i][j] = llinf;
            ll mx = a[i];
            for(ll f = i-1;f>=0;f--){
                v[i][j] = min(v[i][j],v[f][j-1] + mx);
                mx = max(mx,a[f]);
            }
        }
        if(pisi){
            for(ll i = 0;i<=n;i++) cerr<<v[i][j]<< " ";
            cerr<<endl;
        }
    }
    return v[n][k];
}
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
ll rnd(ll l,ll r){
    return uniform_int_distribution<ll>(l,r)(rng);
}
bool gen = 1;
ll b[maxn];
ll dp[maxn][2];
ll dpmin[maxn][2];
ll opt[maxn];
void calc(ll i,ll id){
    if(b[i]==0){
        //if(pisi) cerr<<i<< " "<<get(0,i-1)<<" "<<a[i]<<endl;
        opt[i] = get(0,i-1) + a[i];
        return;
    }
    calc(b[i],id);
    //cerr<<b[i]<< " "<<i-1<< " "<<get(b[i],i-1)<<endl;
    opt[i] = min(opt[b[i]],get(b[i],i-1) + a[i]);
}
int main(){
    test = 1;
    gen = 0;
    pisi = 0;
	ios_base::sync_with_stdio(false);cerr.tie(0);cout.tie(0);cin.tie(0);
    if(gen==0){
        cin >> n >> k;
        for(ll i = 1;i<=n;i++) cin >> a[i];
    }else{
        lol:;
        n = 5000;
        k = 5;
        for(ll i = 1;i<=n;i++) a[i] = rnd(1,1000000);
        if(pisi){
            cerr<<n<< " "<<k<<endl;
            for(ll i = 1;i<=n;i++) cerr<<a[i]<< " ";
            cerr<<endl;
        }
    }
    st[0][0] = 0;
    for(ll i = 1;i<=n;i++) st[i][0] = llinf;
    for(ll j = 1;j<lg;j++){
        for(ll i = 0;i+(1<<j)-1<=n;i++){
            st[i][j] = max(st[i][j-1],st[i+(1<<(j-1))][j-1]);
        }
    }

    for(ll j = 0;j<lg;j++){
        if((1<<j)>n+1) break;
        powi[(1<<j)] = j;
    }
    for(ll i = 1;i<=n;i++){
        if(powi[i]==0) powi[i] = powi[i-1];
    }
    stack<ll> ste;
    for(ll i =1;i<=n;i++){
        while(sz(ste)&&a[i]>a[ste.top()]) ste.pop();
        if(sz(ste)) b[i] = ste.top();
        ste.push(i);
    }
    if(pisi) ceri(b,1,n);
    for(ll i = 1;i<=n;i++) dp[i][0] = llinf;
    dp[0][0] = 0;
    for(ll i = 1;i<=n;i++) dpmin[i][0] = 0;
    for(ll j = 1;j<=k;j++){
        for(ll i = 1;i<=n;i++) opt[i] = llinf;
        dp[0][j] = llinf;
        for(ll i = 1;i<=n;i++){
            calc(i,(j&1)^1);
            dp[i][j&1] = opt[i];
        }
        if(pisi){
            here;
            for(ll i = 0;i<=n;i++) cerr<<dp[i][(j&1)]<<" ";
            cerr<<endl;
            for(ll i = 0;i<=n;i++) cerr<<dp[i][(j&1)^1]<< " ";
            cerr<<endl;
        }
        for(ll i = 0;i<=n;i++) st[i][0] = dp[i][(j&1)];
        for(ll j = 1;j<lg;j++){
            for(ll i = 0;i+(1<<j)-1<=n;i++){
                st[i][j] = min(st[i][j-1],st[i+(1<<(j-1))][j-1]);
            }
        }
        for(ll i = 0;i<=n;i++) dp[i][(j&1)^1] = dp[i][j&1];
        //for(ll i = 0;i<=n;i++) dp[i][(j&1)] = llinf;
    }
    //here;
    here;
    ll ans2 = brut();
    if(test) cerr<<"brut: "<<ans2<<endl;
    //if(ans2==dp[n][(k&1)^1]) goto lol;
    cout<<dp[n][(k&1)^1]<<endl;
	return 0;
}
/*
5 2
1 2 3 4 5
out: 6
5 4
3 1 3 5 1
out: 10
7 4
10 7 4 1 8 4 1
10 5
5 9 2 9 4 6 9 3 7 8
*/

Compilation message (stderr)

blocks.cpp: In function 'int main()':
blocks.cpp:96:9: warning: label 'lol' defined but not used [-Wunused-label]
   96 |         lol:;
      |         ^~~

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