Programming Articles - Page 2195 of 3363

The method references are introduced in Java 8 similar to lambda expression. It can allow us to reference methods or constructors without executing them. The method references and lambda expressions require a target type that consists of a compatible functional interface. We can also use a method reference with generic classes and generic methods in java.Exampleinterface MyFunc {    int func(T[] vals, T v); } class MyArrayOps {    static int countMatching(T[] vals, T v) {       int count = 0;       for(int i=0; i < vals.length; i++)          if(vals[i] == v)             count++;       return count;   ... Read More

A lambda expression can't specify type parameters, so it's not generic. However, a functional interface associated with lambda expression is generic. In this case, the target type of lambda expression has determined by the type of argument(s) specified when a functional interface reference is declared.Syntaxinterface SomeFunc {  T func(T t); }Exampleinterface MyGeneric {    T compute(T t); } public class LambdaGenericFuncInterfaceTest {    public static void main(String args[]) {       MyGeneric reverse = (str) -> {   // Lambda Expression          String result = "";          for(int i = str.length()-1; i >= 0; i--)           ... Read More

Problem statementGiven an array, arr[] find the maximum value of (arr[i] – i) – (arr[j] – j) where i is not equal to j. Where i and j vary from 0 to n-1 and n is the size of input array arr[].If the input array is {7, 5, 10, 2, 3} then we can obtain 9 maximum value as follows−(element 10 – index 2) - (element 2 – index 3) (10 – 2) – (2 – 3) = 8 – (-1) = 9Algorithm1. Find maximum value of (arr[i] – i) in whole array. 2. Find minimum value of (arr[i] – ... Read More

Problem statementGiven three non-zero integers a, b and c. The task is to find the maximum value possible by putting addition and multiplication signs between them in any order.Please note that rearrangement of integers is allowed but addition and multiplication sign must be used once.If a = 1, b = 3 and c = 5 then maximum value will be 20 as follows−(1 + 3) * 5 = 20Algorithm1. If all numbers are positive, then add two small numbers and multiply result with larger one 2. If only two numbers are positive, then multiply 2 positive numbers and add remaining ... Read More

Problem statementGiven an array of N integers. You are allowed to rearrange the elements of the array. The task is to find the maximum value of Σarr[i]*i, where i = 0, 1, 2, .. n – 1.If input array = {4, 1, 6, 2} then the maximum sum will be 28 if we rearrange elements in sorted order−{1, 2, 4, 6} = (1 * 0) + (2 * 1) + (4 * 2) + (6 * 3) = 28Algorithm1. Sort array in ascending order 2. Iterate over array and multiply each array element by 1 where i = 0, 1, ... Read More

Problem statementGiven a rod of length L, the task is to cut the rod in such a way that the total number of segments of length p, q and r is maximized. The segments can only be of length p, q, and rIf l = 15, p = 2, q = 3 and r = 5 then we can make 7 segments as follows −{2, 2, 2, 2, 2, 2, 3}AlgorithmWe can solve this problem using dynamic programming1. Initialize dp[] array to 0 2. Iterate till the length of the rod. For every i, a cut of p, q and ... Read More

Problem statementGiven an unsigned number, find the maximum number that could be formed by using the bits of the given unsigned numberIf the input number is 8 then its binary representation is−00000000000000000000000000001000To maximize it set MSB to 1. Then number becomes 2147483648 whose binary representation is−10000000000000000000000000000000Algorithms1. Count number of set bits in the binary representation of a given number 2. Find a number with n least significant set bits 3. shift the number left by (32 – n)Example Live Demo#include using namespace std; unsigned getMaxNumber(unsigned num){    int n = __builtin_popcount(num);    if (n == 32) {       return num;    }    unsigned result = (1

Problem statementGiven an array arr[] of N elements and an integer K where K < N. The task is to insert K integer elements to the same array such that the median of the resultant array is maximizedIf input array is {1, 3, 2, 5} and k = 3 then −Sorted array becomes {1, 2, 3, 5}Insert 3 elements that are greater than 5. After this operation array becomes {1, 2, 3, 5, 6, 6, 6}Median of the new array is 5Algorithm1. In order to maximize the median of the resultant array, all the elements that need to be inserted ... Read More

Problem statementGiven an array arr[] of N elements and an integer K where K < N. The task is to insert K integer elements to the same array such that the median of the resultant array is maximizedIf input array is {1, 3, 2, 5} and k = 3 then−Sorted array becomes {1, 2, 3, 5}Insert 3 elements that are greater than 5. After this operation array becomes {1, 2, 3, 5, 6, 6, 6}Median of the new array is 5Algorithm1. In order to maximize the median of the resultant array, all the elements that need to be inserted must ... Read More

Problem statementGiven an array arr[] of N integers. The task is to first find the maximum sub-array sum and then remove at most one element from the sub-array. Remove at most a single element such that the maximum sum after removal is maximized.If given input array is {1, 2, 3, -2, 3} then maximum sub-array sum is {2, 3, -2, 3}. Then we can remove -2. After removing the remaining array becomes−{1, 2, 3, 3} with sum 9 which is maximum.Algorithm1. Use Kadane’s algorithm to find the maximum subarray sum. 2. Once the sum has beens find, re-apply Kadane’s algorithm ... Read More