Cod sursa(job #1010665)

Utilizator vld7Campeanu Vlad vld7 Data 15 octombrie 2013 13:24:11
Problema Sortare prin comparare Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.84 kb
#include <fstream>

using namespace std;

ifstream f("algsort.in");
ofstream g("algsort.out");

const int MAX_N = 500005;

int n, a[MAX_N], b[MAX_N];

void merge (int st, int mid, int dr) {
	int i = st, j = mid + 1, k = 0;
	
	while (i <= mid && j <= dr)
		if (a[i] > a[j])
			b[++k] = a[j],	j++;
		else
			b[++k] = a[i],	i++;
		
	if (i > mid)
		for (; j <= dr; j++)
			b[++k] = a[j];
	else
		for (; i <= mid; i++)
			b[++k] = a[i];
		
	for (int x = st, y = 1; x <= dr; x++, y++)
		a[x] = b[y];
}

void mergesort (int st, int dr) {
	if (st == dr)
		return;
	
	int mid = (st + dr) / 2;
	mergesort (st, mid);
	mergesort (mid + 1, dr);
	merge (st, mid, dr);
}

int main() {
	f >> n;
	for (int i = 1; i <= n; i++)
		f >> a[i];
	
	mergesort (1, n);
	
	for (int i = 1; i <= n; i++)
		g << a[i] << " ";
	
	return 0;
}