Java 三角形最小路径和

package Thread;
import java.util.Random;
public class ThreadTest {
public static void main(String agrs[]) {
Random rand = new Random();
int[][] a = new int[4][];
a[0] = new int[1];
a[1] = new int[2];
a[2] = new int[3];
a[3] = new int[4];
for(int i = 0;i < a.length;i++) {
for(int j = 0;j < a[i].length;j++) {
a[i][j] = rand.nextInt(10);
System.out.print(a[i][j]+" ");
}
System.out.println();
}
for(int i = 1;i < a.length;i++) {
for(int j = 0;j < a[i].length;j++) {
if(j == 0) {
a[i][j] = a[i][j] + a[i-1][j];
}
else if(j == a[i].length-1) {
a[i][j] = a[i][j] + a[i-1][j-1];
}
else {
a[i][j] =a[i][j] +
Math.min(a[i-1][j], a[i-1][j-1]);
}
}
}
int min = a[a.length-1][0];
for(int i = 1;i < a[a.length-1].length;i++) {
if(min > a[a.length-1][i])
min = a[a.length-1][i];
}
System.out.println(min);
}
}