Submission #770413

#	Time	Username	Problem	Language	Result	Execution time	Memory
770413		GrindMachine	The Kingdom of JOIOI (JOI17_joioi)	C++17	15 / 100	368 ms	128016 KiB

joioi

// Om Namah Shivaya

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x, y) ((x + y - 1) / (y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i, n) for(int i = 0; i < n; ++i)
#define rep1(i, n) for(int i = 1; i <= n; ++i)
#define rev(i, s, e) for(int i = s; i >= e; --i)
#define trav(i, a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a, b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a, b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif

/*



*/

const int MOD = 1e9 + 7;
const int N = 2e3 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

ll n,m;
ll a[N][N], pmn[N][N], pmx[N][N], smn[N][N], smx[N][N];
ll ans = inf2;
vector<ll> lens;

void go(ll i, ll prev_len, ll mnl, ll mxl, ll mnr, ll mxr){
    if(i > n){
        ll val = max(mxl-mnl, mxr-mnr);
        amin(ans,val);
        // if(val == 19){
        //     debug(lens);
        // }
        return;
    }

    rep(j,m+1){
        if(j < prev_len) conts;
        ll mn1 = inf2, mx1 = -inf2;
        ll mn2 = inf2, mx2 = -inf2;
        rep1(k,m){
            if(k <= j){
                amin(mn1,a[i][k]);
                amax(mx1,a[i][k]);
            }
            else{
                amin(mn2,a[i][k]);
                amax(mx2,a[i][k]);
            }
        }

        lens.pb(j);
        go(i+1, j, min(mnl,mn1), max(mxl,mx1), min(mnr,mn2), max(mxr,mx2));
        lens.pop_back();
    }
}

void solve(int test_case)
{
    cin >> n >> m;
    rep1(i,n) rep1(j,m) cin >> a[i][j];

    memset(pmn,0x10,sizeof pmn);
    memset(smn,0x10,sizeof smn);
    memset(pmx,-0x10,sizeof pmx);
    memset(smx,-0x10,sizeof smx);

    rep1(i,n){
        rep1(j,m){
            pmn[i][j] = min(pmn[i][j-1], a[i][j]);
            pmx[i][j] = max(pmx[i][j-1], a[i][j]);
        }
        rev(j,m,1){
            smn[i][j] = min(smn[i][j+1], a[i][j]);
            smx[i][j] = max(smx[i][j+1], a[i][j]);
        }
    }

    vector<ll> b;
    rep1(i,n){
        rep1(j,m){
            b.pb(a[i][j]);
        }
    }

    sort(all(b));
    b.resize(unique(all(b))-b.begin());

    auto get = [&](ll mn, ll mx){
        ll other_diff = inf2;

        // dec
        {
            ll prev_len = inf2;
            ll other_mn = inf2, other_mx = -inf2;

            rep1(i,n){
                ll len = 0;
                ll l = 1, r = n;
                
                while(l <= r){
                    ll mid = (l+r) >> 1;
                    if(pmn[i][mid] >= mn and pmx[i][mid] <= mx){
                        len = mid;
                        l = mid+1;
                    }
                    else{
                        r = mid-1;
                    }
                }

                amin(len,prev_len);
                prev_len = len;

                amin(other_mn, smn[i][len+1]);
                amax(other_mx, smx[i][len+1]);
            }

            amin(other_diff, other_mx-other_mn);
        }

        // inc
        {
            ll prev_len = inf2;
            ll other_mn = inf2, other_mx = -inf2;

            rev(i,n,1){
                ll len = 0;
                ll l = 1, r = n;
                
                while(l <= r){
                    ll mid = (l+r) >> 1;
                    if(pmn[i][mid] >= mn and pmx[i][mid] <= mx){
                        len = mid;
                        l = mid+1;
                    }
                    else{
                        r = mid-1;
                    }
                }

                amin(len,prev_len);
                prev_len = len;

                amin(other_mn, smn[i][len+1]);
                amax(other_mx, smx[i][len+1]);
            }

            amin(other_diff, other_mx-other_mn);
        }

        return other_diff;
    };

    ll ans = inf2;
    ll ptr = 0;

    rep(ind,sz(b)){
        while(ptr < sz(b)){
            ll res = get(b[ind], b[ptr]);
            ll val = max(b[ptr]-b[ind], res);
            amin(ans,val);
            if(res <= b[ptr]-b[ind]){
                break;
            }
            ptr++;
        }
    }

    cout << ans << endl;
}

int main()
{
    fastio;

    int t = 1;
    // cin >> t;

    rep1(i, t) {
        solve(i);
    }

    return 0;
}

Compilation message (stderr)

joioi.cpp: In function 'void solve(int)':
joioi.cpp:30:36: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   30 | #define rep(i, n) for(int i = 0; i < n; ++i)
      |                                    ^
joioi.cpp:198:5: note: in expansion of macro 'rep'
  198 |     rep(ind,sz(b)){
      |     ^~~
joioi.cpp:199:19: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  199 |         while(ptr < sz(b)){
      |                   ^

• Subtask 1: 15 / 15
• Subtask 2: 0 / 45
• Subtask 3: 0 / 40