oj.uz

Submission #770476

# Submission time Handle Problem Language Result Execution time Memory
770476 2023-07-01T10:09:46 Z GrindMachine The Kingdom of JOIOI (JOI17_joioi) C++17
60 / 100
 4000 ms 188944 KB 
// 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
 
/*
 
refs:
stress tested to identify the bug: https://oj.uz/submission/767335
didnt set the bounds for the binary search properly (wrote n instead of m)

*/

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 = m;
                
                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 = m;
                
                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)){
        assert(ptr >= ind);

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

            if(val == 0){
                cout << 0 << endl;
                return;
            }

            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

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:200:5: note: in expansion of macro 'rep'
  200 |     rep(ind,sz(b)){
      |     ^~~
joioi.cpp:203:19: 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]
  203 |         while(ptr < sz(b)){
      |                   ^

Subtask #1
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 43 ms 126156 KB Output is correct
2 Correct 43 ms 126156 KB Output is correct
3 Correct 42 ms 126108 KB Output is correct
4 Correct 43 ms 126160 KB Output is correct
5 Correct 43 ms 126148 KB Output is correct
6 Correct 47 ms 126172 KB Output is correct
7 Correct 41 ms 126156 KB Output is correct
8 Correct 41 ms 126136 KB Output is correct
9 Correct 41 ms 126164 KB Output is correct
10 Correct 42 ms 126120 KB Output is correct
11 Correct 41 ms 126188 KB Output is correct
12 Correct 41 ms 126156 KB Output is correct
13 Correct 48 ms 126156 KB Output is correct
14 Correct 41 ms 126156 KB Output is correct

Subtask #2
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 43 ms 126156 KB Output is correct
2 Correct 43 ms 126156 KB Output is correct
3 Correct 42 ms 126108 KB Output is correct
4 Correct 43 ms 126160 KB Output is correct
5 Correct 43 ms 126148 KB Output is correct
6 Correct 47 ms 126172 KB Output is correct
7 Correct 41 ms 126156 KB Output is correct
8 Correct 41 ms 126136 KB Output is correct
9 Correct 41 ms 126164 KB Output is correct
10 Correct 42 ms 126120 KB Output is correct
11 Correct 41 ms 126188 KB Output is correct
12 Correct 41 ms 126156 KB Output is correct
13 Correct 48 ms 126156 KB Output is correct
14 Correct 41 ms 126156 KB Output is correct
15 Correct 42 ms 126292 KB Output is correct
16 Correct 46 ms 127836 KB Output is correct
17 Correct 290 ms 127864 KB Output is correct
18 Correct 289 ms 127876 KB Output is correct
19 Correct 306 ms 127904 KB Output is correct
20 Correct 250 ms 127744 KB Output is correct
21 Correct 288 ms 127856 KB Output is correct
22 Correct 341 ms 127848 KB Output is correct
23 Correct 323 ms 127952 KB Output is correct
24 Correct 246 ms 127828 KB Output is correct
25 Correct 310 ms 127892 KB Output is correct
26 Correct 282 ms 127960 KB Output is correct
27 Correct 326 ms 127848 KB Output is correct
28 Correct 312 ms 127952 KB Output is correct

Subtask #3
0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 43 ms 126156 KB Output is correct
2 Correct 43 ms 126156 KB Output is correct
3 Correct 42 ms 126108 KB Output is correct
4 Correct 43 ms 126160 KB Output is correct
5 Correct 43 ms 126148 KB Output is correct
6 Correct 47 ms 126172 KB Output is correct
7 Correct 41 ms 126156 KB Output is correct
8 Correct 41 ms 126136 KB Output is correct
9 Correct 41 ms 126164 KB Output is correct
10 Correct 42 ms 126120 KB Output is correct
11 Correct 41 ms 126188 KB Output is correct
12 Correct 41 ms 126156 KB Output is correct
13 Correct 48 ms 126156 KB Output is correct
14 Correct 41 ms 126156 KB Output is correct
15 Correct 42 ms 126292 KB Output is correct
16 Correct 46 ms 127836 KB Output is correct
17 Correct 290 ms 127864 KB Output is correct
18 Correct 289 ms 127876 KB Output is correct
19 Correct 306 ms 127904 KB Output is correct
20 Correct 250 ms 127744 KB Output is correct
21 Correct 288 ms 127856 KB Output is correct
22 Correct 341 ms 127848 KB Output is correct
23 Correct 323 ms 127952 KB Output is correct
24 Correct 246 ms 127828 KB Output is correct
25 Correct 310 ms 127892 KB Output is correct
26 Correct 282 ms 127960 KB Output is correct
27 Correct 326 ms 127848 KB Output is correct
28 Correct 312 ms 127952 KB Output is correct
29 Execution timed out 4094 ms 188944 KB Time limit exceeded
30 Halted 0 ms 0 KB -