java 杨辉三角形求解答

Question

打印一个10行的杨辉三角形，编译通过运行总是说数组索引超出界限异常，求问问题出在哪。。
运行后的提示：Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: -1 at yanghui.main(yanghui.java:11)
public class yanghui{
public static void main(String[] args){
int a[][]=new int[10][];
for(int i = 0; i < a.length; i++){
a[i] = new int[i+1];
for(int j = 0; i < a[i].length; j++){
if(j == 0 || j == a[i].length-1){
a[i][j] = 1;
}
else{
a[i][j] = a[i-1][j] + a[i-1][j-1];
}
}
}
for(int i = 0; i < a.length; i++){
for(int j = 0; j < a[i].length; j++){
System.out.print(a[i][j]+" ");
}
System.out.println("");
}
}
}

Answer 1

for(int j = 0; i < a[i].length; j++){
改为
for(int j = 0; j< a[i].length; j++){
中间的j你写成i啦