Cod sursa(job #2700802)

Utilizator vnedelcuVictor Andrei Nedelcu vnedelcu Data 28 ianuarie 2021 20:41:26
Problema Subsir crescator maximal Scor 65
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.6 kb
#include <fstream>
#include <vector>

using namespace std;

int search_insertion_pos
(
    vector<int> & longest_inc_subseq,
    int longest_inc_subseq_len,
    int val
) {
    int left = 0;
    int right = longest_inc_subseq_len - 1;

    if (val > longest_inc_subseq[right]) {
        return right + 1;
    }

    while (left <= right) {
        int mid = left + (right - left) / 2;

        if (
            ((mid > 0 && val > longest_inc_subseq[mid - 1]) ||
            (mid == 0)) && 
            val <= longest_inc_subseq[mid]
        ) {
            return mid;
        } else if (mid > 0 && val <= longest_inc_subseq[mid - 1]) {
            right = mid - 1;
        } else {
            left = mid + 1;
        }
    }
}

int main() {
    int N;

    ifstream fin("scmax.in");
    fin >> N;
    vector<int> a(N);
    for (int i = 0; i < N; i++) {
        fin >> a[i];
    }
    fin.close();

    vector<int> longest_inc_subseq(N, -1);
    longest_inc_subseq[0] = a[0];
    int longest_inc_subseq_len = 1;

    for (int i = 1; i < N; i++) {
        int insertion_pos = search_insertion_pos(
            longest_inc_subseq,
            longest_inc_subseq_len,
            a[i]
        );
        longest_inc_subseq[insertion_pos] = a[i];
        if (insertion_pos == longest_inc_subseq_len) {
            longest_inc_subseq_len++;
        }
    }

    ofstream fout("scmax.out");
    fout << longest_inc_subseq_len << endl;
    for (int i = 0; i < longest_inc_subseq_len; i++) {
        fout << longest_inc_subseq[i] << " ";
    }
    fout.close();

    return 0;
}