CareerCup

the idea for this one is binary search to find low bound (row) and upper bound (col) for the
2-d array

private int getlength(String target){
		int count = 0 ;
		for (char c : target.toCharArray()) {
			if (c != ' ') {
				count++;
			}
		}
		return count ;
	}
	
	public void createSquare (String target){
		int len = getlength(target) ;		
		if (len == 0) {
			return ;
		}
		long low = 1 , high = len ;
		while (low + 1 < high) {
		  long mid = low + (high - low) / 2 ;
		  if (mid * mid < len ) {
			  low = mid ;
		  } else{
			  high = mid ;
		  }
		}
		char [][] ch = null ;
		int row = 0 , col = 0 ;
		if (high * high == len) {
			row = (int) high ;
			col = (int) high ;
			ch = new char[row][col];
		} else if (low * low == len) {
			row = (int) low ;
			col = (int) low ;
			ch = new char[(int)row][(int)col];
		} else{
			row = (int) low ;
			col = (int) high ;
			ch = new char[(int)row][(int)col];
		}
		createMatrix (ch, target);
		display (ch);
	}
	
	private void createMatrix (char [][] matrix, String word){
		int row = matrix.length , col = matrix[0].length;
		int i = 0 , j = 0 , p = 0;
		while (i < row) {
			j = 0 ;
		  	while (p < word.length() && j < col) {
		  		if (word.charAt(p) != ' ') {
		  		   matrix[i][j++] = word.charAt(p) ;	
		  		}
		  		p++;
		  	}
		  	i++;
		}
	}
	
	private void display (char [][] matrix){
		int row = matrix.length , col = matrix[0].length;
		for (int i = 0 ; i < row ; ++i)  {
		 for (int j = 0 ; j < col ; ++j)  {
			 if (matrix[i][j] != '\u0000') {
				 System.out.print(matrix[i][j]);	 
			 }
			 
		 }
		 System.out.println();
		}
	}

void main()
{
   char* input = "if man was meant to stay on the ground god would have given us roots";
   char* spaceless = new char[strlen(input)];
   for (int i = 0, j = 0; !i || input[i-1]; i++)
      if (input[i] != ' ')
         spaceless[j++] = input[i];
   int numRow = (int)sqrt((float)strlen(spaceless));
   int lastRow = strlen(spaceless) - numRow*numRow + 1;
   int numCol = numRow + (lastRow != 0);
   for (int i = 0; i < numCol; i++, printf(" "))
      for (int j = 0; j < numRow; j++)
         if ((j < numRow - 1) || (i < lastRow))
            printf("%c", spaceless[j*numCol + i]);    
   getch();
};

output:

imtgdvs fearwer mayoogo anouuio ntnnlvt wttddes aohghn sseoau

}

StringBuilder resultString = new StringBuilder();
		String[] words = sentence.split("\\s+");
		StringBuilder allWords = new StringBuilder(sentence.length());
		for (String word : words){
			allWords.append(word.toLowerCase());
		}
		int counter = 0 , allWordsLength = allWords.length();

		while (counter < allWordsLength){
			int upper = counter + 8;
			if (upper < allWordsLength){
				resultString.append(allWords.substring(counter, upper)+" ");
			}else{
				resultString.append(allWords.substring(counter));
			}
			counter += 8;
		}
		return resultString.toString();

One classic method for composing secret messages is called a square code. The spaces are removed from the English text and the characters are written into a square (or rectangle). For example, the sentence "If man was meant to stay on the ground god would have given us roots" is 54 characters long, so it is written into a rectangle with 7 rows and 8 columns.
ifmanwas
meanttos
tayonthe
groundgo
dwouldha
vegivenu
sroots
The coded message is obtained by reading down the columns going left to right. For example, the message above is coded as:

#include <stdio.h>
#include "square.h"

int main () {
char *msg;
int length;

for (int i = 0 ; i < get_number_of_messages(); i++) {
msg = read_message(i);
length = get_message_length(i);

for (int i = 0; i < length; i++) {
printf("%c", msg[i]);
}

printf("\n");
}

return 0;
}