Submission #548797

#	Time	Username	Problem	Language	Result	Execution time	Memory
548797		Belgutei	Safety (NOI18_safety)	C++17	9 / 100	40 ms	2180 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
 
ll n,h;
ll a[200005];
ll dp[10005];
ll tur[10005];
 
ll level,zereg[30];
vector<ll> v[30];
ll l,r;
ll mn;
ll mn1,mx1;
 
void build_tree(){
    zereg[0] = 1;
    for(int i = 0; i <= 30; i++){
        if(zereg[i] >= 5000){
            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<=5000; 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);
}

ll solve(int pos){
    int cnt=0;
    ll ret=0;
    for(int i=mn1; i<=mx1; i++){
        dp[i] = abs(i-a[pos]);
    }
    for(int i = pos - 1; i >= 1; i--){
        cnt++;
        ll zero=0;
        ret = 1e18;
        for(int j=max(a[i]-cnt*h,zero); j<=a[i]+cnt*h; j++){
            tur[j]=dp[j];
            dp[j] = 1e18;
        }
         for(int j=max(a[i]-cnt*h,zero); j<=a[i]+cnt*h; j++){
            l=max(j-h,mn1);
            r=min(j+h,mx1);
            for(int k=l; k<=r; k++){
                dp[k] = tur[j] + abs(j-a[i]);
                ret=min(ret,dp[k]);
            }
        }
    }
    debug(ret);
    //
    for(int i=mn1; i<=mx1; i++){
        dp[i] = abs(i-a[pos]);
    }
    cnt = 0;
    ll ret1=0;
    for(int i = pos + 1; i <= n; i++){
        cnt++;
        ll zero=0;
        ret1 = 1e18;
        for(int j=max(a[pos]-cnt*h,mn1); j<=min(a[pos]+cnt*h,mx1); j++){
            debug(j);
            tur[j]=dp[j];
            dp[j] = 1e18;
        }
        for(int j=max(a[pos]-(cnt-1)*h,mn1); j<=min(a[pos]+(cnt-1)*h,mx1); j++){
            l=max(j-h,mn1);
            r=min(j+h,mx1);
            for(int k=l; k<=r; k++){
                dp[k] = min(dp[k], tur[j] + abs(k-a[i]));
                ret1=min(ret1,dp[k]);
            }
        }
    }
    debug(ret1);
    return ret + ret1;
}
 
 
int main() {
    IOS
    cin >> n >> h;
    mn1 = 1e9;
    for(int i = 1; i <= n; i++){
        cin >> a[i];
        mn1 = min(mn1,a[i]);
        mx1 = max(mx1,a[i]);
    }
    debug(mn1);
    debug(mx1);
    if(n <= 10 && h <= 2){ // subtask 3
        ll ans = 1e18;
        for(int i = 1; i <= n; i++){
            // i - behlegdsen number
            ans=min(ans,solve(i));
            break;
        }
        cout << ans;
        return 0;
    }
    if(h==0){
        sort(a+1,a+n+1);
        ll ans = 1e18;
        ll sum = 0;
        for(int i = 1; i <= n; i++){
            sum += a[i];
        }
        ll pre_sum = 0;
        for(int i = 1; i <= n; i++){
            sum -= a[i];
            ll tur = a[i] * (i-1);
            tur = tur - pre_sum;
            ll tur1 = a[i] * (n-i);
            tur1 = sum - tur1;
            ans=min(ans,tur + tur1);
            pre_sum += a[i];
        }
        cout << ans;
        return 0;
    }
    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 = mn1; j <= mx1; j++){
            // (j-h) -> (j+h)

            l = max(j-h,mn1);
            r = min(j+h,mx1);
            mn=1e9;
            dfs(0,0);
            dp[j] = min(dp[j],mn+abs(a[i]-j));
        }
    }
    ll ans = 1e9;
    for(int i=0; i<=5000; i++){
        ans=min(ans,dp[i]);
    }
    cout << ans;
}

Compilation message (stderr)

safety.cpp: In function 'long long int solve(int)':
safety.cpp:103:12: warning: unused variable 'zero' [-Wunused-variable]
  103 |         ll zero=0;
      |            ^~~~

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