原文:
给定大小为 n * n 的正方形矩阵 mat[][] 。任务是打印位于给定矩阵的次对角线上的所有元素。 例:
输入: mat[][] = { {1，2，3}， {3，3，4，}， {2，4，6}} 输出:3 4 t9】输入: mat[][] = { {1，2，3，4}， {3，3，4，4}， {2，4，6，3}， {1
方法:正方形矩阵的次对角线是位于构成主对角线的元素正下方的元素集。对于主对角线元素，它们的索引类似于(i = j)，对于次对角线元素，它们的索引类似于 i = j 1 (i 表示行，j 表示列)。 因此元素 arr[1][0]，arr[2][1]，arr[3][2]，arr[4][3]，…。是亚对角线的元素。 要么遍历矩阵的所有元素，只打印 i = j 1 的那些需要 o(n 2 )时间复杂度的元素，要么只打印从 1 到 row count–1 的遍历行，并将元素打印为 arr[row][row–1]。 以下是上述方法的实施:
c
// c implementation of the approach
#include
using namespace std;
#define r 4
#define c 4
// function to print the sub diagonal
// elements of the given matrix
void printsubdiagonal(int arr[r][c])
{
for (int i = 1; i < r; i ) {
cout << arr[i][i - 1] << " ";
}
}
// driver code
int main()
{
int arr[r][c] = { { 1, 2, 3, 4 },
{ 5, 6, 7, 8 },
{ 9, 10, 11, 12 },
{ 13, 14, 15, 16 } };
printsubdiagonal(arr);
return 0;
}
java 语言(一种计算机语言，尤用于创建网站)
// java implementation of the approach
import java.io.*;
class gfg
{
static int r = 4;
static int c = 4;
// function to print the sub diagonal
// elements of the given matrix
static void printsubdiagonal(int arr[][])
{
for (int i = 1; i < r; i )
{
system.out.print(arr[i][i - 1] " ");
}
}
// driver code
public static void main (string[] args)
{
int arr[][] = { { 1, 2, 3, 4 },
{ 5, 6, 7, 8 },
{ 9, 10, 11, 12 },
{ 13, 14, 15, 16 } };
printsubdiagonal(arr);
}
}
// this code is contributed by ajit.
python 3
# python3 implementation of the approach
r = 4
c = 4
# function to print the sub diagonal
# elements of the given matrix
def printsubdiagonal(arr):
for i in range(1, r):
print(arr[i][i - 1], end = " ")
# driver code
arr = [[ 1, 2, 3, 4 ],
[ 5, 6, 7, 8 ],
[ 9, 10, 11, 12 ],
[ 13, 14, 15, 16 ]]
printsubdiagonal(arr);
# this code is contributed
# by mohit kumar
c
// c# implementation of the approach
using system;
class gfg
{
static int r = 4;
static int c = 4;
// function to print the sub diagonal
// elements of the given matrix
static void printsubdiagonal(int[,] arr)
{
for (int i = 1; i < r; i )
{
console.write(arr[i, i - 1] " ");
}
}
// driver code
public static void main ()
{
int [,]arr = {{ 1, 2, 3, 4 },
{ 5, 6, 7, 8 },
{ 9, 10, 11, 12 },
{ 13, 14, 15, 16 }};
printsubdiagonal(arr);
}
}
// this code is contributed by codemech.
java 描述语言
output:
5 10 15
麻将胡了pg电子网站的版权属于：月萌api www.moonapi.com，转载请注明出处
