Submission #650366

#	Time	Username	Problem	Language	Result	Execution time	Memory
650366		rafatoa	Unscrambling a Messy Bug (IOI16_messy)	C++17	0 / 100	461 ms	524288 KiB

messy

#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
typedef long double ld;
#pragma GCC optimize ("Ofast")

#define double ld
const int inf = 2e9;
const int INF = 4e18;
const int mod = 1e9+7;

#define F first
#define S second
#define vi vector<int>
#define vvi vector<vi>
#define pi pair<int, int>
#define vpi vector<pi>
#define vb vector<bool>
#define vvb vector<vb>
#define pb push_back
#define read(a) for(auto &x:a) cin >> x;
#define print(a) for(auto x:a) cout << x << " "; cout << "\n";
#define rs resize
#define as assign
#define vc vector<char>
#define vvc vector<vc>
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()

#define ppb pop_back
#define MP make_pair

// #define int ll
void add_element(string x);
void compile_set();
bool check_element(string x);

int* restore_permutation(int n, int w, int r){
    int p[n];

    function<void(int, int)> add = [&](int l, int r){
        if(l == r) return;
        for(int j=l; j<l+(r-l+1)/2; j++){
            string s;
            for(int i=0; i<n; i++)
                if(i < l || i > r || i == j) s += '1';
                else s += '0';
            add_element(s);
        }
        add(l, l+(r-l+1)/2-1);
        add(l+(r-l+1)/2, r);
    };

    add(0, n-1);

    compile_set();

    function<void(int, int, vi)> solve = [&](int l, int r, vi v){
        if(l == r){
            p[n-1-l] = n-1-v[0];
            return;
        }
        vi a, b;
        for(auto &x:v){
            string s;
            for(int i=0; i<n; i++){
                if(i != x && binary_search(all(v), i)) s += '0';
                else s += '1';
            }
            if(check_element(s)) a.pb(x);
            else b.pb(x);
        }
        solve(l, l+(r-l+1)/2-1, a);
        solve(l+(r-l+1)/2, r, b);
    };

    vi v; iota(all(v), 0);
    solve(0, n-1, v);

    return p;
}

/*stolen stuff you should look for
    * int overflow, array bounds
    * special cases (n=1?)
    * READ CONSTRAINTS
    * do smth instead of nothing and stay organized
    * WRITE STUFF DOWN
    * DON'T GET STUCK ON ONE APPROACH
*/

Compilation message (stderr)

messy.cpp:9:17: warning: overflow in conversion from 'double' to 'int' changes value from '4.0e+18' to '2147483647' [-Woverflow]
    9 | const int INF = 4e18;
      |                 ^~~~
messy.cpp: In function 'int* restore_permutation(int, int, int)':
messy.cpp:80:12: warning: address of local variable 'p' returned [-Wreturn-local-addr]
   80 |     return p;
      |            ^
messy.cpp:39:9: note: declared here
   39 |     int p[n];
      |         ^

• Subtask 1: 0 / 20
• Subtask 2: 0 / 18
• Subtask 3: 0 / 11
• Subtask 4: 0 / 21
• Subtask 5: 0 / 30