java 杨辉三角

try{

int n = 10;

int mat[][] = new int
[];

int i, j;

for (i = 0; i < n; i++) {

mat[i] = new int[i + 1];

//mat[i][0] = 1;

mat[i][i] = 1;

for (j = 1; j < i; j++) {

mat[i][j] = mat[i - 1][j - 1] + mat[i - 1][j];

}

}

for (i = 0; i < mat.length; i++) {

for (j = 0; j < n - i; j++)

System.out.print(" ");

for (j = 0; j < mat[i].length; j++)

System.out.print(" " + mat[i][j]);

System.out.println();

}

}catch(Exception e){

e.printStackTrace();

}