Cod sursa(job #3285061)

Utilizator voaidesrVoaides Robert voaidesr Data 12 martie 2025 14:55:31
Problema Sortare prin comparare Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.28 kb
// https://www.infoarena.ro/problema/algsort 
#include <fstream>
#include <vector>
using namespace std;


ifstream cin("algsort.in");
ofstream cout("algsort.out");

void merge(vector<int>& arr, int left, int middle, int right) {

    int s1 = middle - left + 1;
    int s2 = right - middle;

    vector <int> v1(s1), v2(s2);

    // copy elements
    for(int i = 0; i < s1; i ++)
        v1[i] = arr[left + i];
    for(int i = 0; i < s2; i++)
        v2[i] = arr[middle + 1 + i];

    // merge vectors 
    // merged into arr[left, right]
    int i = 0, j = 0, k = left;
    while(i < s1 && j < s2)
        if(v1[i] <= v2[j])
            arr[k++] = v1[i++];
        else
            arr[k++] = v2[j++];
    
    while(i < s1)
        arr[k++] = v1[i++];
    
    while(j < s2)
        arr[k++] = v2[j++];
}

void merge_sort(vector<int>& arr, int left, int right) {
    if (left >= right) return;
    int mid = left + (right - left)/2; // prevent overflow
    merge_sort(arr, left, mid);
    merge_sort(arr, mid + 1, right);
    merge(arr, left, mid, right);
}   

int main() {
    int n;
    cin >> n;
    vector <int> v(n); // declare vector of size n
    for(int i = 0; i < n; i ++)
        cin >> v[i];
    merge_sort(v, 0, n-1);
    for(int i = 0; i < n; i++)
        cout << v[i] << " ";
    return 0;
}