Submission #1076714

#	Time	Username	Problem	Language	Result	Execution time	Memory
1076714		steveonalex	The Kingdom of JOIOI (JOI17_joioi)	C++17	100 / 100	364 ms	70484 KiB

joioi

// #include "aliens.h"
#include <bits/stdc++.h>
 
using namespace std;
 
typedef long long ll;
typedef unsigned long long ull;
 
#define MASK(i) (1LL << (i))
#define GETBIT(mask, i) (((mask) >> (i)) & 1)
#define ALL(v) (v).begin(), (v).end()
#define block_of_code if(true)
 
ll max(ll a, ll b){return (a > b) ? a : b;}
ll min(ll a, ll b){return (a < b) ? a : b;}
ll gcd(ll a, ll b){return __gcd(a, b);}
ll lcm(ll a, ll b){return a / gcd(a, b) * b;}
 
ll LASTBIT(ll mask){return (mask) & (-mask);}
int pop_cnt(ll mask){return __builtin_popcountll(mask);}
int ctz(ull mask){return __builtin_ctzll(mask);}
int logOf(ull mask){return 63 - __builtin_clzll(mask);}
 
mt19937_64 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
ll rngesus(ll l, ll r){return l + (ull) rng() % (r - l + 1);}
double rngesus_d(double l, double r){
    double cur = rngesus(0, MASK(60) - 1);
    cur /= MASK(60) - 1;
    return l + cur * (r - l);
}
 
template <class T1, class T2>
    bool maximize(T1 &a, T2 b){
        if (a < b) {a = b; return true;}
        return false;
    }
 
template <class T1, class T2>
    bool minimize(T1 &a, T2 b){
        if (a > b) {a = b; return true;}
        return false;
    }
 
template <class T>
    void printArr(T container, string separator = " ", string finish = "\n", ostream &out = cout){
        for(auto item: container) out << item << separator;
        out << finish;
    }
 
template <class T>
    void remove_dup(vector<T> &a){
        sort(ALL(a));
        a.resize(unique(ALL(a)) - a.begin());
    }

const int N = 2002;
int n, m;
int a[N][N], b[N][N];
int dp[N][N];
 
int main(void){
    ios::sync_with_stdio(0);cin.tie(0); cout.tie(0);
    clock_t start = clock();

    cin >> n >> m;
    for(int i= 1; i<=n; ++i) 
    for(int j = 1; j<=m; ++j) cin >> a[i][j];

    int mi = 1e9, ma = 0;
    for(int i = 1; i<=n; ++i) for(int j = 1; j<=m; ++j) {
        minimize(mi, a[i][j]);
        maximize(ma, a[i][j]);
    }

    // cout << mi << " " << ma << "\n";

    int ans = 1e9;
    for(int x = 0; x < 4; ++x){
        for(int i = 1; i<=n; ++i) for(int j = 1; j<=m; ++j) b[i][j] = a[i][j];

        if (GETBIT(x, 0)){
            for(int i = 1; i<=n; ++i) reverse(b[i] + 1, b[i] + m + 1);
        }
        if (GETBIT(x, 1)) {
            for(int i = 1; i<=n/2; ++i) {
                for(int j= 1; j<=m; ++j) swap(b[i][j], b[n - i + 1][j]);
            }
        }

        vector<int> dp(m+1);
        for(int i= 1; i<=n; ++i){
            vector<int> cu(m+1);
            int cur = 0;
            for(int j = 1; j<=m; ++j){
                maximize(cur, b[i][j] - mi);
                maximize(cu[j], cur);
            }
            cur = 0;
            for(int j = m; j>=1; --j){
                maximize(cur, ma - b[i][j]);
                maximize(cu[j-1], cur);
            }
            for(int j = 0; j<=m; ++j) maximize(dp[j], cu[j]);
            for(int j = m-1; j>=0; --j) minimize(dp[j], dp[j+1]);
        }
        minimize(ans, dp[0]);
    }

    cout << ans << "\n";
 
    cerr << "Time elapsed: " << clock() - start << " ms\n";
    return 0;
}

• Subtask 1: 15 / 15
• Subtask 2: 45 / 45
• Subtask 3: 40 / 40