How do I place a vector in descending order?
public static void vetor() {
int[] vet = {
7,
4,
10,
8,
2,
5
};
Arrays.sort(vet);
//Comando para colocar em ordem decrescente.
for (int i = 0; i < vet.length; i++) {
System.out.println(vet[i] + "");
}
}
To sort an array in descending order, you can use the sort algorithm bubble sort :
for (int i = 1; i < vet.length; i++) {
for (int j = 0; j < i; j++) {
if (vet[i] > vet[j]) {
int temp = vet[i];
vet[i] = vet[j];
vet[j] = temp;
}
}
}
There are two loops that compare the two-in-two values of the array, when a value in the posterior position is greater than the value in the previous position (% cos_de%), it changes both positions. And so it goes on comparing even the last two elements.
See working at IDEONE
Another interesting solution I found in SOEn is this:
for(int i=0;i<vet.length;i++) {
vet[i]=-vet[i];
}
Arrays.sort(vet);
for(int i=0;i<vet.length;i++) {
vet[i]=-vet[i];
}
The above code does:
The result is the same, as can be seen in the ideone .
How about doing this?
Arrays.sort(vet);
int[] vetAux;
int contador = 0;
for(int i=vet.length - 1;i >= 0;i--) {
vetAux[contador]=vet[i];
contador++;
}
//Ordem Decrescente
import java.util.Scanner;
public class OrdemDecrescente {
public static void main(String[] args) {
int cont = 1;
int[] vet = new int[5];
Scanner sc = new Scanner(System.in);
for (int i = 0; i < vet.length; i++){
System.out.print("Digite "+cont+"° número: \t");
vet[i] = sc.nextInt();
cont++;
}
for (int i = 1; i < vet.length; i++) {
for (int j = 0; j < i; j++) {
if (vet[i] > vet[j]) {
int aux = vet[i];
vet[i] = vet[j];
vet[j] = aux;
}
}
}
System.out.println("Array em ordem decrescente:");
for (int n : vet) {
System.out.print(n + " ");
}
}
}