Printing the boundary elements of the matrix is one of the basic questions of the matrix. In this post we will see how can we print the boundary elements.
Input : { {1,3,9,0,2},{4,7,1,4,6},{0,9,6,3,4}}
Output : 1,3,9,0,2,6,4,,3,6,9,0,4
So as we see in the image above we have to write a program through which we can print the boundary elements of the matrix .
We have two codes for this problem one in java and one in c++.
Java Code :
public class Matrix
{
public static void printBoundary(int [][] mat,int rows , int cols)
{
if(rows==1)
{
for(int i=0;i<cols;i++)
System.out.println(mat[0][i]+" ");
}
else{
if(cols==1){
for(int i=0;i<rows;i++)
System.out.println(mat[i][0]+" ");
}
else{
for(int i=0;i<cols;i++)
System.out.print(mat[0][i]+" ");
for(int i=1;i<rows;i++)
System.out.print(mat[i][cols-1]+" ");
for(int i=cols-2;i>=0;i--)
System.out.print(mat[rows-1][i]+" ");
for(int i=rows-2;i>0;i--)
System.out.print(mat[i][0]+" ");
}
}
}
public static void main(String [] args)
{
int [][] mat = { {1,2,3},{3,4,5},{7,2,0},{9,5,3}};
System.out.println("------------------");
printBoundary(mat, 4, 3);
}
}
C++ Code :
#include<iostream>
public class Matrix
{
public static void printBoundary(int [][] mat,int rows , int cols)
{
if(rows==1)
{
for(int i=0;i<cols;i++)
cout<<(mat[0][i]+" ");
}
else{
if(cols==1){
for(int i=0;i<rows;i++)
cout<<(mat[i][0]+" ");
}
else{
for(int i=0;i<cols;i++)
cout<<(mat[0][i]+" ");
for(int i=1;i<rows;i++)
cout<<(mat[i][cols-1]+" ");
for(int i=cols-2;i>=0;i--)
cout<<(mat[rows-1][i]+" ");
for(int i=rows-2;i>0;i--)
cout<<(mat[i][0]+" ");
}
}
}
}
int main()
{
int [][] mat = { {1,2,3},{3,4,5},{7,2,0},{9,5,3}};
cout<<"------------------";
printBoundary(mat, 4, 3);
return 0;
}
