1. One-dimensional array
(1)int[] $i = new int[4];
(2)double[] _d = {1.3, 2.9, 3.6, 4.2};
2. Two-dimensional array
(1)float[][] f = new float[3][4];
(2)char[][] c = {{'a', 'b'}, {'c', 'd', 'e', 'f'}, {'g', 'h', 'i'}};
(3) Initialization can first define the number of arrays, and then allocate space for each array
String[][] s = new String[3][];
s[0] = new String[2];
s[1] = new String[4];
s[2] = new String[3];
3、sort
import java.util.Array;
Arrays.sort(_d);
4. Bubble sort
for (int i = 0; i < _d.length - 1; i++) {
for (int j = 0; j < _d.length - 1; j++) {
if (_d[j] > _d[j+1]) {
double d = _d[j];
_d[j] = _d[j+1];
_d[j+1] = d;
}
}
}
5. Selection sort
for (int i = 0; i < _d.length - 1; i++) {
for (int j = i + 1; j < _d.length; j++) {
if (_d[i] > _d[j]) {
double d = _d[i];
_d[i] = _d[j];
_d[j] = d;
}
}
}