PROGRAMMING:Constructing lower triangular matrix
The lower triangular matrix is a matrix with all zeros at the top right of the main diagonal.
Enter the integer n (1 ≤ n ≤ 10) to construct an n × The lower triangular values of N are 1, 2, 3. Output the constructed matrix.
Hint: all 0 matrix can be obtained by initialization, such as: int a [3] [3] = {0}; We can get a 3 with all zeros × 3 matrix.
###Input format:
Enter n.
###Output format:
n × Matrix of n
Each number takes up 3 squares, and there are n rows in total.
###Input example:
```in
five
```
###Output example:
```out
1 0 0 0 0
2 3 0 0 0
4 5 6 0 0
7 8 9 10 0
11 12 13 14 15
```
answer：If there is no answer, please comment
Enter the integer n (1 ≤ n ≤ 10) to construct an n × The lower triangular values of N are 1, 2, 3. Output the constructed matrix.
Hint: all 0 matrix can be obtained by initialization, such as: int a [3] [3] = {0}; We can get a 3 with all zeros × 3 matrix.
###Input format:
Enter n.
###Output format:
n × Matrix of n
Each number takes up 3 squares, and there are n rows in total.
###Input example:
```in
five
```
###Output example:
```out
1 0 0 0 0
2 3 0 0 0
4 5 6 0 0
7 8 9 10 0
11 12 13 14 15
```
answer：If there is no answer, please comment