Submission #1058938

#	Time	Username	Problem	Language	Result	Execution time	Memory
1058938		vjudge1	Bigger segments (IZhO19_segments)	C++17	73 / 100	332 ms	262144 KiB

segments

#include <bits/stdc++.h>
#ifdef LOCAL
    #include "/home/trcmai/code/tools.h"
    #define debug(x...) cerr << "\e[91m"<<__func__<<":"<<__LINE__<<" [" << #x << "] = ["; _print(x); cerr << "\e[39m" << endl;
#else
    #define debug(x...)
#endif
using namespace std;
#define all(a) a.begin(), a.end()
#define ll long long
#define int long long
#define endl '\n'
const int N = 5e5 + 6, LOG = 27, MOD = 1e9 + 7;
const ll INF = 1e18;
int n;

struct dynamic_segment_tree
{
    struct node {ll v, l, r; node() {v = 0; l = -1, r = -1;}};
    vector<node> st;
    dynamic_segment_tree() {st.clear(); st.push_back(node());};
    void update(long long id, long long l, long long r, long long i, ll x)
    {
        if (l == r) {st[id].v = max(st[id].v,x); return;}
        long long m = (r+l)>>1; st[id].v = max(st[id].v,x);
        if (l <= i && i <= m)
        {
            if (st[id].l == -1) {st[id].l = st.size(); st.push_back(node());}
            update(st[id].l,l,m,i,x);
        }
        if (m < i && i <= r)
        {
            if (st[id].r == -1) {st[id].r = st.size(); st.push_back(node());}
            update(st[id].r,m+1,r,i,x);
        }
    }
    ll get(long long id, long long l, long long r, long long u, long long v)
    {
        if (r < u || v < l) return 0;
        if (u <= l && r <= v) return st[id].v;
        long long m = (r+l)>>1; ll val = 0;
        if (st[id].l != -1) val = max(val,get(st[id].l,l,m,u,v));
        if (st[id].r != -1) val = max(val,get(st[id].r,m+1,r,u,v));
        return val;
    }
    void update(long long i, ll x) {update(0,0,1e17,i,x);}
    ll get(long long u, long long v) {return get(0,0,1e17,u,v);}
};
ll a[N],dp[N],opt[N];
signed main() {
    cin.tie(0)->sync_with_stdio(0);
    auto solver=[&](){
        cin>>n; 
        for(int i = 1;i <= n;++i){
            cin>>a[i];
            a[i] += a[i - 1];
        }
        dynamic_segment_tree st;
        for(int i = 1;i <= n;++i){
            int j = st.get(0,a[i]);
            dp[i] = dp[j] + 1; 
            opt[i] = a[i] - a[j]; 
            st.update(opt[i] + a[i],i);
        }
        cout<<dp[n]<<endl;
    };
    int t = 1; // cin>>t;
    while (t--) solver();
}

• Subtask 1: 13 / 13
• Subtask 2: 14 / 14
• Subtask 3: 10 / 10
• Subtask 4: 36 / 36
• Subtask 5: 0 / 27