Check that if given number is expressed sum of consecutive or not

The given problem is to check whether a given number can be expressed as the sum of two or more consecutive numbers. For example, the number 9 can be expressed as 4 + 5 or 2 + 3 + 4, but the number 4 cannot be expressed as the sum of any two or more consecutive numbers.

Problem Statement

Given an integer 'num', we need to determine if 'num' can be expressed as the sum of two or more consecutive numbers.

Example

Let's take a few examples to better understand the problem:

1. For 'num' = 9: The consecutive sums of 9 are:

   • 2 + 3 + 4 = 9
   • 4 + 5 = 9

2. For 'num' = 4: The consecutive sums of 4 are:

   • There are no two or more consecutive numbers that add up to 4.

Pseudocode

// Function to check whether given number is sum of consecutive two or more numbers
consecutive_sum(num):
    // Check if the number is negative, if yes, return
    if num < 0:
        return

    // Print the given number
    print "Number:", num

    // Check if the number is not 0 and not a power of 2
    if num != 0 AND ((num AND (num - 1)) != 0):
        print "Yes"
    else:
        print "No"

// Main function
main():
    // Call the consecutive_sum function with example numbers
    consecutive_sum(9)
    consecutive_sum(4)

1. We start by defining the function 'consecutive_sum(num)' to check if a given number can be expressed as the sum of two or more consecutive numbers.
2. Within the function, we check if the 'num' is less than 0. If it is negative, we return from the function since negative numbers cannot be expressed as the sum of consecutive numbers.
3. Next, we print the given number to display it in the output.
4. We then check if 'num' is not equal to 0 and whether 'num' is not a power of 2 (using the bitwise AND operation and subtraction). If this condition is true, it means 'num' can be expressed as the sum of two or more consecutive numbers, so we print "Yes".
5. If the condition in step 4 is false, it means 'num' cannot be expressed as the sum of two or more consecutive numbers, and we print "No".
6. The main function 'main()' is called to test the 'consecutive_sum()' function with example numbers, which are 9 and 4 in this case.

Algorithm Explanation

1. We begin by defining the 'consecutive_sum(num)' function.
2. We handle the case where 'num' is negative, and in such cases, we return without further processing, as negative numbers cannot be expressed as the sum of two or more consecutive numbers.
3. Next, we check if 'num' is not equal to 0 and whether (num & (num - 1)) is not equal to 0. This bitwise operation checks if 'num' is not a power of 2.
4. If 'num' is not a power of 2, it means 'num' can be expressed as the sum of two or more consecutive numbers, and we print "Yes".
5. Otherwise, if 'num' is a power of 2 or 0, it cannot be expressed as the sum of two or more consecutive numbers, and we print "No".

Code Solution

Here given code implementation process.

• C
• Java
• C++
• C#
• Php
• Node Js
• Python
• Ruby
• Scala
• Swift 4
• Kotlin

// C program 
// Check that if given number is expressed sum of consecutive or not
#include <stdio.h>

// Check whether given number is sum of consecutive two or more numbers 
void consecutive_sum(int num)
{
	if (num < 0)
	{
		return;
	}
	// Given number
	printf("\n Number : %d", num);
	if (num != 0 && ((num & (num - 1)) != 0))
	{
		printf("\n Yes ");
	}
	else
	{
		printf("\n No ");
	}
}
int main(int argc, char
	const *argv[])
{
	consecutive_sum(9);
	consecutive_sum(4);
	return 0;
}

 Number : 9
 Yes
 Number : 4
 No

/*
  Java program
  Check that if given number is expressed sum of consecutive or not
*/
public class Consecutive
{
	// Check whether given number is sum of consecutive two or more numbers 
	public void consecutiveSum(int num)
	{
		if (num < 0)
		{
			return;
		}
		// Given number
		System.out.print("\n Number : " + num);
		// Check that number is constructed by two or more consecutive numbers or not
		if (num != 0 && ((num & (num - 1)) != 0))
		{
			// When Yes
			System.out.print("\n Yes ");
		}
		else
		{
			System.out.print("\n No ");
		}
	}
	public static void main(String[] args)
	{
		Consecutive task = new Consecutive();
		// num = 9
		//     = 4+5 (consecutive number)
		task.consecutiveSum(9);
		// num = 4
		task.consecutiveSum(4);
	}
}

 Number : 9
 Yes
 Number : 4
 No

// Include header file
#include <iostream>
using namespace std;

/*
  C++ program
  Check that if given number is expressed sum of consecutive or not
*/

class Consecutive
{
	public:
		// Check whether given number is sum of consecutive two or more numbers
		void consecutiveSum(int num)
		{
			if (num < 0)
			{
				return;
			}
			// Given number
			cout << "\n Number : " << num;
			// Check that number is constructed by two or more consecutive numbers or not
			if (num != 0 && ((num &(num - 1)) != 0))
			{
				// When Yes
				cout << "\n Yes ";
			}
			else
			{
				cout << "\n No ";
			}
		}
};
int main()
{
	Consecutive task = Consecutive();
	// num = 9
	//     = 4+5 (consecutive number)
	task.consecutiveSum(9);
	// num = 4
	task.consecutiveSum(4);
	return 0;
}

 Number : 9
 Yes
 Number : 4
 No

// Include namespace system
using System;
/*
  C# program
  Check that if given number is expressed sum of consecutive or not
*/
public class Consecutive
{
	// Check whether given number is sum of consecutive two or more numbers
	public void consecutiveSum(int num)
	{
		if (num < 0)
		{
			return;
		}
		// Given number
		Console.Write("\n Number : " + num);
		// Check that number is constructed by two or more consecutive numbers or not
		if (num != 0 && ((num & (num - 1)) != 0))
		{
			// When Yes
			Console.Write("\n Yes ");
		}
		else
		{
			Console.Write("\n No ");
		}
	}
	public static void Main(String[] args)
	{
		Consecutive task = new Consecutive();
		// num = 9
		//     = 4+5 (consecutive number)
		task.consecutiveSum(9);
		// num = 4
		task.consecutiveSum(4);
	}
}

 Number : 9
 Yes
 Number : 4
 No

<?php
/*
  Php program
  Check that if given number is expressed sum of consecutive or not
*/
class Consecutive
{
	// Check whether given number is sum of consecutive two or more numbers
	public	function consecutiveSum($num)
	{
		if ($num < 0)
		{
			return;
		}
		// Given number
		echo "\n Number : ". $num;
		// Check that number is constructed by two or more consecutive numbers or not
		if ($num != 0 && (($num & ($num - 1)) != 0))
		{
			// When Yes
			echo "\n Yes ";
		}
		else
		{
			echo "\n No ";
		}
	}
}

function main()
{
	$task = new Consecutive();
	// num = 9
	//     = 4+5 (consecutive number)
	$task->consecutiveSum(9);
	// num = 4
	$task->consecutiveSum(4);
}
main();

 Number : 9
 Yes
 Number : 4
 No

/*
  Node Js program
  Check that if given number is expressed sum of consecutive or not
*/
class Consecutive
{
	// Check whether given number is sum of consecutive two or more numbers
	consecutiveSum(num)
	{
		if (num < 0)
		{
			return;
		}
		// Given number
		process.stdout.write("\n Number : " + num);
		// Check that number is constructed by two or more consecutive numbers or not
		if (num != 0 && ((num & (num - 1)) != 0))
		{
			// When Yes
			process.stdout.write("\n Yes ");
		}
		else
		{
			process.stdout.write("\n No ");
		}
	}
}

function main()
{
	var task = new Consecutive();
	// num = 9
	//     = 4+5 (consecutive number)
	task.consecutiveSum(9);
	// num = 4
	task.consecutiveSum(4);
}
main();

 Number : 9
 Yes
 Number : 4
 No

#   Python 3 program
#   Check that if given number is expressed sum of consecutive or not

class Consecutive :
	#  Check whether given number is sum of consecutive two or more numbers 
	def consecutiveSum(self, num) :
		if (num < 0) :
			return
		
		#  Given number
		print("\n Number : ", num, end = "")
		#  Check that number is constructed by two or more consecutive numbers or not
		if (num != 0 and((num & (num - 1)) != 0)) :
			#  When Yes
			print("\n Yes ", end = "")
		else :
			print("\n No ", end = "")
		
	

def main() :
	task = Consecutive()
	#  num = 9
	#      = 4+5 (consecutive number)
	task.consecutiveSum(9)
	#  num = 4
	task.consecutiveSum(4)

if __name__ == "__main__": main()

 Number :  9
 Yes
 Number :  4
 No

#   Ruby program
#   Check that if given number is expressed sum of consecutive or not

class Consecutive 
	#  Check whether given number is sum of consecutive two or more numbers 
	def consecutiveSum(num) 
		if (num < 0) 
			return
		end

		#  Given number
		print("\n Number : ", num)
		#  Check that number is constructed by two or more consecutive numbers or not
		if (num != 0 && ((num & (num - 1)) != 0)) 
			#  When Yes
			print("\n Yes ")
		else 
			print("\n No ")
		end

	end

end

def main() 
	task = Consecutive.new()
	#  num = 9
	#      = 4+5 (consecutive number)
	task.consecutiveSum(9)
	#  num = 4
	task.consecutiveSum(4)
end

main()

 Number : 9
 Yes 
 Number : 4
 No 

/*
  Scala program
  Check that if given number is expressed sum of consecutive or not
*/
class Consecutive
{
	// Check whether given number is sum of consecutive two or more numbers
	def consecutiveSum(num: Int): Unit = {
		if (num < 0)
		{
			return;
		}
		// Given number
		print("\n Number : " + num);
		// Check that number is constructed by two or more consecutive numbers or not
		if (num != 0 && ((num & (num - 1)) != 0))
		{
			// When Yes
			print("\n Yes ");
		}
		else
		{
			print("\n No ");
		}
	}
}
object Main
{
	def main(args: Array[String]): Unit = {
		var task: Consecutive = new Consecutive();
		// num = 9
		//     = 4+5 (consecutive number)
		task.consecutiveSum(9);
		// num = 4
		task.consecutiveSum(4);
	}
}

 Number : 9
 Yes
 Number : 4
 No

/*
  Swift 4 program
  Check that if given number is expressed sum of consecutive or not
*/
class Consecutive
{
	// Check whether given number is sum of consecutive two or more numbers
	func consecutiveSum(_ num: Int)
	{
		if (num < 0)
		{
			return;
		}
		// Given number
		print("\n Number : ", num, terminator: "");
		// Check that number is constructed by two or more consecutive numbers or not
		if (num  != 0 && ((num & (num - 1))  != 0))
		{
			// When Yes
			print("\n Yes ", terminator: "");
		}
		else
		{
			print("\n No ", terminator: "");
		}
	}
}
func main()
{
	let task: Consecutive = Consecutive();
	// num = 9
	//     = 4+5 (consecutive number)
	task.consecutiveSum(9);
	// num = 4
	task.consecutiveSum(4);
}
main();

 Number :  9
 Yes
 Number :  4
 No

/*
  Kotlin program
  Check that if given number is expressed sum of consecutive or not
*/
class Consecutive
{
	// Check whether given number is sum of consecutive two or more numbers
	fun consecutiveSum(num: Int): Unit
	{
		if (num < 0)
		{
			return;
		}
		// Given number
		print("\n Number : " + num);
		// Check that number is constructed by two or more consecutive numbers or not
		if (num != 0 && ((num and(num - 1)) != 0))
		{
			// When Yes
			print("\n Yes ");
		}
		else
		{
			print("\n No ");
		}
	}
}
fun main(args: Array < String > ): Unit
{
	var task: Consecutive = Consecutive();
	// num = 9
	//     = 4+5 (consecutive number)
	task.consecutiveSum(9);
	// num = 4
	task.consecutiveSum(4);
}

 Number : 9
 Yes
 Number : 4
 No

Explanation of Output

1. For 'num' = 9, the output is "Yes" because 9 can be expressed as the sum of two or more consecutive numbers (2 + 3 + 4 or 4 + 5).

2. For 'num' = 4, the output is "No" because 4 cannot be expressed as the sum of two or more consecutive numbers.

Time Complexity

The time complexity of the given code is O(1). This is because the 'consecutive_sum' function performs some basic operations that do not depend on the input size. The bitwise AND and subtraction operations are constant-time operations, and thus the overall time complexity remains constant.