Programming Articles - Page 2528 of 3366

A prime number is a number greater than 1 that is divisible only by 1 and itself. Given a number N, our task is to print all alternate prime numbers up to N. This means we skip every second prime number and only print the 1st position, 3rd position, 5th position, and so on. Let's look at the example scenarios to understand the problem clearly: Scenario 1 Input: N = 15 Output: 2 5 11 Explanation: Prime numbers up to 15 are: 2, 3, 5, 7, 11, 13 Taking alternate primes (1st, 3rd, 5th): 2, 5, 11 Scenario 2 ... Read More

Aliquot sum in C++ Aliquot sum of a positive integer n is the sum of all proper divisors of n. A positive proper divisor is a divisor of a number, excluding the number itself. For example, for n = 6; 1, 2, 3 are positive proper divisors but 6 itself is not. Scenario 1 Input: n = 20 Output: 22 Explanation: Proper divisors of 20 are: 1, 2, 4, 5, 10 Sum of proper divisors are: 1 + 2 + 4 + 5 + 10 = 22 So, aliquot sum of 20 is : 22 Scenario 2 Input: 15 ... Read More

Here we will see how we can shut down the system by writing a simple C or C++ code. The shutdown process varies in different OS. If we are Linux user, we can use this terminal command to shut down.shutdown –P nowIf we are using Windows system, we can use this command −c:\windows\system32\shutdown /iWe will see the code for Linux and WindowsExample(Linux)#include using namespace std; int main() {    system("shutdown -P now"); }Example(Windows)#include using namespace std; int main() {    system("c:\windows\system32\shutdown /i "); }

Here we will see how we can check number of set bits in an integer number. The set bits are 1’s in the binary representation of a number. For an example the number 13 has three set bits 1101. So the count will be 3.To solve this problem, we will shift the number to the right, and if the LSb is 1, then increase count. Until the number becomes 0, it will run.AlgorithmcountSetBit()begin    count := 0    while count is not 0, do       if LSb of n is set, then          count := ... Read More

The inversions of an array indicate; how many changes are required to convert the array into its sorted form. When an array is already sorted, it needs 0 inversions, and in other case, the number of inversions will be maximum, if the array is reversed.To solve this problem, we will follow the Merge sort approach to reduce the time complexity, and make it in Divide and Conquer algorithm.InputA sequence of numbers. (1, 5, 6, 4, 20).OutputThe number of inversions required to arrange the numbers into ascending order.Here the number of inversions are 2. First inversion: (1, 5, 4, 6, 20) ... Read More

Here we will see how to count number of matchsticks are required to make the pyramid-like below. The base of the pyramid is given. So if the base is 1, it will take 3 matchsticks to make a pyramid, for base 2, 9 matchsticks are needed, for base size 3, it will take 18 matchsticks.To solve this problem, we have to use this formula −Example Live Demo#include using namespace std; int main(){    int x;    cout > x;    int count = 3*x*(x+1)/2;    cout

In this section, we will see one interesting problem. There are N coins. we have to find what is the max height we can make if we arrange the coins as pyramid. In this fashion, the first row will hold 1 coin, second will hold 2 coins and so on.In the given diagram, we can see to make a pyramid of height three we need minimum 6 coins. We cannot make height 4 until we have 10 coins. Now let us see how to check the maximum height.We can get the height by using this formula.Example Live Demo#include #include using namespace ... Read More

In C++, we can use 32-bit character representations. The c32rtomb() function is used to convert 32-bit character representation to narrow multi-byte character representation. We can find this function inside the uchar.h header file.This function takes three parameters. These are −The string where multi-byte character will be stored32-bit character to convertThe pointer of type mbstate_t object. which is used to interpret multibyte string.This function returns number of bytes written to the character array, when it is successful, otherwise returns -1. Let us see an example to get better idea.Example Live Demo#include #include #include using namespace std; int main() { ... Read More

In C++, we can use 16-bit character representations. The c16rtomb() function is used to convert 16-bit character representation to narrow multi-byte character representation. We can find this function inside the uchar.h header file.This function takes three parameters. These are −The string where multi-byte character will be stored16-bit character to convertThe pointer of type mbstate_t object. which is used to interpret multibyte string.This function returns number of bytes written to the character array, when it is successful, otherwise returns -1. Let us see an example to get better idea.Example Live Demo#include #include #include using namespace std; int main() { ... Read More

Here we will see some good tricks of C++ programming language that can help us in different area. Like if we want to participate in some competitive programming events, then these tricks will help us to reduce the time for writing codes. Let us see some of these examples one by one.Checking whether a number is odd or even without using % operator. This trick is simple. We can perform bitwise AND operation with the number and 1. If the result is non-zero then this is odd, otherwise this is even. The logic is too simple. All odd numbers have ... Read More