Coding Ninjas java Code

Author: ashu1230

2D Arrays/LargestRowOrColumn.java

@@ -0,0 +1,81 @@
+import java.util.Scanner;
+public class Solution {
+    
+    public static int[][] takeInput()
+	{
+		
+		Scanner sc = new Scanner(System.in);
+		//System.out.println("Enter R: ");
+		int r = sc.nextInt();
+		//System.out.println("Enter C: ");
+		int c = sc.nextInt();
+        
+        if(r==0 & c==0)
+        {
+            System.out.println("row 0 -2147483648");
+           
+        }
+		else if(r>0 && c>0){
+		int arr[][]=new int[r][c];
+		
+		for(int i = 0;i<r;i++)
+		{
+			for(int j = 0;j<c;j++)
+			{
+				//System.out.println("Enter "+i+"th row "+j+"th element");
+				arr[i][j]=sc.nextInt();
+			}
+		}
+        }
+		return arr;
+	}
+
+	public static void findLargest(int mat[][]){
+		//Your code goes here
+        int maxc= Integer.MIN_VALUE;
+        int ci = 0;
+		
+		int r = mat.length;
+		int c = mat[0].length;
+		
+		for(int j=0;j<c;j++)
+		{	int sum = 0;
+			for(int i = 0;i<r;i++)
+			{	
+				sum+=mat[i][j];	
+			}
+			if(sum>maxc)
+			{
+				maxc = sum;
+                ci = j;
+				
+			}
+			
+		}
+		
+        int maxr = Integer.MIN_VALUE;
+        int ri = 0;
+        for(int i = 0;i<r;i++)
+        {	int sum = 0;
+            for(int j = 0;j<c;j++)
+            {
+                sum+=mat[i][j];
+            }
+         	if(sum>maxr)
+         	{
+             maxr=sum;
+             ri=i;
+         	}
+        }
+        
+        if(maxr>=maxc)
+        {
+            System.out.println("row "+ri+" "+maxr);
+        }
+        else
+        {
+            System.out.println("column "+ci+" "+maxc);
+        }
+	}
+
+}

2D Arrays/PrintLikeAWave.java

@@ -0,0 +1,46 @@
+
+public class Solution {
+
+	public static void wavePrint(int mat[][]){
+		//Your code goes here
+        
+        //the case when row = 0 and column = 0
+        if(mat.length == 0){
+            return;
+        }
+		int r = mat.length;
+		int c = mat[0].length;
+        
+        if(r==0 && c==0)
+        {
+            System.out.print(" ");
+            
+        }
+        else
+        {
+		
+		for(int j=0;j<c;j++)
+		{	
+			
+			if(j%2==0)
+			{ 	int i=0;
+				while(i<r)
+				{
+					System.out.print(mat[i][j]+" ");
+					i++;
+				}
+			}
+			else
+			{
+				int i = r-1;
+				while(i>=0)
+				{
+					System.out.print(mat[i][j]+" ");
+					i--;
+				}
+			}
+			
+        }
+		}
+	}
+}

2D Arrays/PrintSpiral.java

@@ -0,0 +1,62 @@
+
+public class Solution {
+
+	public static void spiralPrint(int matrix[][]){
+		//Your code goes here
+        
+        if(matrix.length == 0)
+        {
+            return;
+        }
+		int rs = 0;
+		int re = matrix.length-1;
+		int cs = 0;
+		int ce = matrix[0].length - 1;
+		int n = matrix.length;
+		int m = matrix[0].length;
+		int count = 1;
+		
+		while(count<=(n*m))
+		{
+			int i = rs;
+			int j = cs;
+			while(j<=ce)
+			{
+				System.out.print(matrix[rs][j]+" "); //1 2 3 4 
+				j++;
+				count++;
+			}
+			rs++;
+			i++;
+			while(i<=re)
+			{
+				System.out.print(matrix[i][ce]+" "); // 1 2 3 4 5 6 7 8
+				i++;
+				count++;
+				
+			}
+			ce--;
+			int k = ce;
+			while(k>=cs)
+			{
+				System.out.print(matrix[re][k]+" ");// 1 2 3 4 5 6 7 8 9 10 11
+				k--;
+				count++;
+			}
+			
+			re--;
+			int l = re;
+			while(l>=rs)
+			{
+				System.out.print(matrix[l][cs]+" "); // 1 2 3 4 5 6 7 8 9 10 11 12 13 14 
+				l--;
+				count++;
+			}
+			cs++;
+			
+		}
+    }
+}
+		
+		
+		

2D Arrays/RowWiseSum.java

@@ -0,0 +1,30 @@
+import java.util.Scanner;
+public class Solution {
+
+	public static void rowWiseSum(int[][] mat) {
+	  int row = mat.length;
+        int col = mat[0].length;
+        
+        int sum=0;
+        for(int i = 0;i<row;i++)
+        {
+            for(int j = 0;j<col;j++)
+            {	
+                sum+=mat[i][j];
+            }
+            System.out.print(sum+" ");
+            sum = 0;
+        }
+        
+	}
+    public static void main(String[] args) {
+		// TODO Auto-generated method stub
+		Scanner sc = new Scanner(System.in);
+		int r = sc.nextInt();
+		int c = sc.nextInt();
+		int arr[][] = new int[r][c];
+		rowWiseSum(arr);
+
+	}
+
+}

2D Arrays/TotalSum.java

@@ -0,0 +1,107 @@
+import java.util.Scanner;
+import java.util.Arrays;
+public class Solution {
+
+
+	public static void totalSum(int[][] mat) {
+		//Your code goes here
+        int r = mat.length;
+		int c = mat[0].length;
+
+		int all[] = new int[40]; //arraylist
+		int sum = 0;
+		int k =0;
+		//row boundaries
+		for(int i = 0;i<1;i++)
+		{
+			for(int j = 0;j<c;j++)
+			{
+
+				all[k]=mat[i][j];
+				k++;
+			}
+		}
+
+		for(int i = r-1;i<r;i++)
+		{
+			for(int j = 0;j<c;j++)
+			{
+
+				all[k]=mat[i][j];
+				k++;
+			}
+		}
+		//column boundaries
+		for(int j=0;j<1;j++)
+		{
+			for(int i = 0; i<r;i++)
+			{
+				all[k]=mat[i][j];
+				k++;
+			}
+		}
+
+		for(int j=c-1;j<c;j++)
+		{
+			for(int i = 0; i<r;i++)
+			{
+				all[k]=mat[i][j];
+				k++;
+			}
+		}
+		//diagonals 
+		for(int i = 0;i<r;i++)
+		{
+			for(int j = 0;j<c;j++)
+			{
+				if(i==j)
+				{
+					all[k]=mat[i][j];
+					k++;
+				}
+			}
+		}
+
+		for(int j = c-1;j>=0;j--)
+		{
+			all[k]=mat[r-j-1][j];
+			k++;
+		}
+		//removing duplicates from array
+		Arrays.sort(all);
+
+//		for(int i = 0;i<all.length;i++)
+//		{
+//			System.out.print(all[i]+" ");
+//		}
+		int n = all.length;
+		int zeroi = 0;
+
+		for(int i = 0;i<n;i++)
+		{
+			if(all[i]!=0)
+			{	
+				zeroi=i;
+				break;
+			}
+		}
+		//System.out.println(zeroi);
+
+		sum=all[zeroi];
+		for(int i=zeroi+1;i<n;i++){
+			if(all[i]==all[i-1]){
+				continue;
+			}
+			else
+			{
+				sum+=all[i];
+			}
+
+		}
+		System.out.println(sum);
+
+
+	}
+        
+	}
+

Arrays-1/ArrangeNumbersInJava.java

@@ -0,0 +1,31 @@
+
+public class Solution {
+    
+   public static int[] arrange(int n) {
+		
+		int[] arr=new int[n];
+		int left=0,right=n-1,counter=1;
+		while(left<=right) {
+			if(counter%2==1) {
+				arr[left++]=counter;
+			}else {
+				arr[right--]=counter;
+			}
+			counter++;
+		}
+		
+	
+		return arr;
+		
+		
+	}
+
+	public static void main(String[] args) {
+		// TODO Auto-generated method stub
+		int[] arr=arrange(11);
+		for(int i : arr) {
+			System.out.print(i+" ");
+		}
+	}
+
+}

Arrays-1/ArrayIntersection.java

@@ -0,0 +1,33 @@
+
+public class Solution{  
+    
+    public static void intersections(int arr1[], int arr2[]) {
+	    	
+	        int n1=arr1.length;
+	    	int n2=arr2.length;
+	   
+	    	
+	    	
+	    	for(int i = 0;i<n1;i++)
+	    	{
+	    		for(int j=0;j<n2;j++)
+	    		{
+	    			if(arr1[i]==arr2[j])
+	    			{
+	    				System.out.print(arr1[i]+" ");
+                        arr2[j]=Integer.MAX_VALUE;
+	    				break;
+	    			}
+	    		}
+	    	}
+	 
+	 }
+	
+	public static void main(String[] args) {
+		// TODO Auto-generated method stub
+		int arr1[] = {2,6,1,2};
+		int arr2[] = {1,2,3,4,2};
+		intersections(arr1,arr2); // output 2 1 2
+	}
+
+}