Submission #887057

# Submission time Handle Problem Language Result Execution time Memory
887057 2023-12-13T14:51:14 Z nnhzzz Watching (JOI13_watching) C++14
100 / 100
312 ms 30296 KB
/* [Author: Nguyen Ngoc Hung] - From THPT Ngo Gia Tu with Love */

#include <algorithm>
#include <bitset>
#include <complex>
#include <deque>
#include <exception>
#include <fstream>
#include <functional>
#include <iomanip>
#include <ios>
#include <iosfwd>
#include <iostream>
#include <istream>
#include <iterator>
#include <limits>
#include <locale>
#include <map>
#include <new>
#include <numeric>
#include <ostream>
#include <queue>
#include <set>
#include <unordered_set>
#include <sstream>
#include <stack>
#include <stdexcept>
#include <streambuf>
#include <string>
#include <utility>
#include <valarray>
#include <vector>
#include <cstring>
#include <unordered_map>
#include <cmath>
#include <array>
#include <cassert>
#include <random>
#include <chrono>

using namespace std;

#define        __nnhzzz__  signed main()
#define          BIT(i,j)  (((i)>>(j))&1LL)
#define           MASK(i)  (1LL<<(i))
#define            ALL(x)  (x).begin(),(x).end()
#define             SZ(x)  (int)(x).size()
#define                fi  first
#define                se  second
#define                ll  long long
#define                ld  long double
#define                vi  vector<int>
#define               vvi  vector<vi>
#define              vvvi  vector<vvi>
#define               pii  pair<int,int>
#define              vpii  vector<pii>
#define             vvpii  vector<vpii>
#define REPDIS(i,be,en,j)  for(int i = (be); i<=(en); i+=j)
#define     REPD(i,be,en)  for(int i = (be); i>=(en); i--)
#define      REP(i,be,en)  for(int i = (be); i<=(en); i++)
#define              endl  "\n"
#define                MP  make_pair
#define               int  ll

//-----------------------------------------------------------------------------------------------//
int readInt(){
    char c;
    do{ c = getchar(); }while(c!='-' && !isdigit(c));
    bool neg = (c=='-');
    int res = neg?0:c-'0';
    while(isdigit(c=getchar())) res = (res<<3)+(res<<1)+(c-'0');
    return neg?-res:res;
}
//------------------------------------------------------------------------------------------------//
const  ll   LINF = 1e18;
const int    INF = 1e9;
const int    LOG = 20;
const int   MAXN = 2e3+7;
const int      N = 1e2+3;
const int    MOD = 1e9+7;
const int   BASE = 1e5;
const  ld    EPS = 1e-9;
const  ld     PI = acos(-1);
const int OFFSET = 1e3;
//------------------------------------------------------------------------------------------------//
template<typename T1, typename T2> bool mini(T1 &a, T2 b){if(a>b){a=b;return true;}return false;}
template<typename T1, typename T2> bool maxi(T1 &a, T2 b){if(a<b){a=b;return true;}return false;}
template<typename T> T gcd(T a, T b) { while(b) { a %= b; swap(a,b); } return a; }
template<typename T> T lcm(T a, T b) { return a/gcd(a,b)*b; }
//------------------------------------------------------------------------------------------------//

/*
----------------------------------------------------------------
    END OF TEMPLATE
----------------------------------------------------------------
    Nguyen Ngoc Hung - nnhzzz
    Training for VOI24 gold medal
----------------------------------------------------------------
*/

int n,p1,p2;
int a[MAXN],f[MAXN][2];
vvi dp;

int calc(int i, int cnt){
    if(cnt>p1) return INF;
    if(i>n) return 0LL;
    int &res = dp[i][cnt];
    if(res!=-1) return res;
    res = min(calc(f[i][0],cnt+1),calc(f[i][1],cnt)+1);
    return res;
}

bool ok(int mid){
    dp.assign(n+3,vi(p1+3,-1));
    REP(i,1,n){
        f[i][0] = upper_bound(a+i+1,a+n+1,a[i]+mid-1)-a;
        f[i][1] = upper_bound(a+i+1,a+n+1,a[i]+2*mid-1)-a;
    }
    return calc(1,0)<=p2;
}

void solve(){
    cin >> n >> p1 >> p2;
    REP(i,1,n) cin >> a[i];
    sort(a+1,a+n+1);
    if(p1+p2>=n){
        cout << 1;
        return ;
    }
    int l = 0,r = 1e9,res = 0;
    while(l<=r){
        int mid = (l+r)>>1;
        if(ok(mid)==true){
            r = mid-1;
            res = mid;
        }else{
            l = mid+1;
        }
    }
    cout << res;
}

__nnhzzz__{
    ios::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    #define task "test"
    if(fopen(task".inp","r")){
        freopen(task".inp","r",stdin);
        freopen(task".out","w",stdout);
    }
    #define task1 "nnhzzz"
    if(fopen(task1".inp","r")){
        freopen(task1".inp","r",stdin);
        freopen(task1".out","w",stdout);
    }

    int test = 1;

    while(test--){
      solve();
    }
    cerr << "\nTime elapsed: " << 1000*clock()/CLOCKS_PER_SEC << "ms\n";
    return 0;
}

/**  /\_/\
 *  (= ._.)
 *  / >TL \>AC
**/

Compilation message

watching.cpp: In function 'int main()':
watching.cpp:149:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  149 |         freopen(task".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
watching.cpp:150:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  150 |         freopen(task".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
watching.cpp:154:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  154 |         freopen(task1".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
watching.cpp:155:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  155 |         freopen(task1".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 1 ms 348 KB Output is correct
10 Correct 1 ms 348 KB Output is correct
11 Correct 1 ms 348 KB Output is correct
12 Correct 1 ms 348 KB Output is correct
13 Correct 1 ms 348 KB Output is correct
14 Correct 0 ms 456 KB Output is correct
15 Correct 0 ms 348 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 3 ms 604 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 1 ms 476 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 1 ms 348 KB Output is correct
7 Correct 6 ms 744 KB Output is correct
8 Correct 22 ms 2648 KB Output is correct
9 Correct 90 ms 12484 KB Output is correct
10 Correct 312 ms 30296 KB Output is correct
11 Correct 23 ms 1880 KB Output is correct
12 Correct 188 ms 16040 KB Output is correct
13 Correct 3 ms 604 KB Output is correct
14 Correct 3 ms 860 KB Output is correct
15 Correct 4 ms 856 KB Output is correct