Submission #57732

#	Time	Username	Problem	Language	Result	Execution time	Memory
57732		Benq	Baloni (COCI15_baloni)	C++14	70 / 100	2063 ms	107424 KiB

baloni

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

using namespace std;
using namespace __gnu_pbds;
 
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;

typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;

typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<cd> vcd;

template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;

#define FOR(i, a, b) for (int i=a; i<(b); i++)
#define F0R(i, a) for (int i=0; i<(a); i++)
#define FORd(i,a,b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i,a) for (int i = (a)-1; i >= 0; i--)

#define sz(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()

const int MOD = 1000000007;
const ll INF = 1e18;
const int MX = 1000001;

int N, a[MX], ans;
bitset<MX> done;
set<int> tmp[MX];

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin >> N;
    FOR(i,1,N+1) {
        cin >> a[i];
        tmp[a[i]].insert(i);
    }
    FOR(i,1,N+1) if (!done[i]) {
        ans ++;
        int cur = i;
        while (1) {
            tmp[a[cur]].erase(cur); done[cur] = 1;
            auto it = tmp[a[cur]-1].lb(cur);
            if (it == tmp[a[cur]-1].end()) break;
            cur = *it;
        }
    }
    cout << ans;
}

/* Look for:
* the exact constraints (multiple sets are too slow for n=10^6 :( ) 
* special cases (n=1?)
* overflow (ll vs int?)
* array bounds
*/

• Subtask 1: 70 / 100