Submission #548744

#	Time	Username	Problem	Language	Result	Execution time	Memory
548744		Belgutei	Safety (NOI18_safety)	C++17	13 / 100	2062 ms	2124 KiB

safety

#include<bits/stdc++.h>

using namespace std;

#define ll long long
#define ff first
#define ss second
#define pb push_back
#define mk make_pair
#define IOS ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); 

void debug_out() { cerr << endl; }
template<typename Head, typename... Tail> void debug_out(Head H, Tail... T) { cerr << ' ' << H; debug_out(T...); }
#ifdef BE_DEBUG
#define debug(...) cerr << "\033[1;31m(" << #__VA_ARGS__ << "):\033[0m", debug_out(__VA_ARGS__)
#else
#define debug(...)
#endif

int n,h;
int a[200005];
int dp[10005];
int tur[10005];

int level,zereg[30];
vector<int> v[30];
int l,r;
int mn;

void build_tree(){
    zereg[0] = 1;
    for(int i = 0; i <= 30; i++){
        if(zereg[i] >= 400){
            level = i;
            break;
        }
        zereg[i+1] = zereg[i] * 2;
    }
    for(int i=0; i<=level; i++){
        for(int j=0; j<zereg[i]; j++){
            v[i].pb(1e9);
        }
    }
}

void tree(){
    for(int i=0; i<=400; i++){
        v[level][i] = dp[i];
        dp[i] = 1e9;
    }
    for(int i=level-1; i>=0; i--){
        for(int j=0; j<zereg[i]; j++){
            v[i][j]=min(v[i+1][j*2],v[i+1][j*2+1]);
        }
    }
}

void dfs(int k, int x){
    int y=zereg[level-k]*x;
    int z=zereg[level-k]*(x+1)-1;
    if(l<=y && z<=r){
        mn = min(mn,v[k][x]);
        return;
    }
    if(z<l || y>r || k==level) return;
    dfs(k+1,x*2);
    dfs(k+1,x*2+1);
}


int main() {
    IOS
    cin >> n >> h;
    for(int i = 1; i <= n; i++){
        cin >> a[i];
    }
    build_tree();
    for(int i = 0; i <= 8192; i++){
        dp[i] = abs(i - a[1]);
    }
    for(int i = 2; i <= n; i++){
        tree();
        for(int j = 0; j <= 400; j++){
            // (j-h) -> (j+h)
            l = max(j-h,0);
            r = min(j+h,400);
            mn=1e9;
            dfs(0,0);
            dp[j] = min(dp[j],mn+abs(a[i]-j));
        }
    }
    int ans = 1e9;
    for(int i=0; i<=400; i++){
        ans=min(ans,dp[i]);
    }
    cout << ans;
}

• Subtask 1: 3 / 3
• Subtask 2: 4 / 4
• Subtask 3: 0 / 9
• Subtask 4: 0 / 5
• Subtask 5: 6 / 6
• Subtask 6: 0 / 11
• Subtask 7: 0 / 11
• Subtask 8: 0 / 22
• Subtask 9: 0 / 29