JavaTpoint Interview Questions and Answers

Calculate the sum of all elements in an array of length N.

• Read the size of the array N and then read N integers as elements of the array.

• Iterate through the array and add each element to a running sum.

• Return the final sum as the output.

Remove duplicate occurrences of characters in a given string.

• Use a hash set to keep track of characters seen so far.

• Iterate through the string and add non-duplicate characters to a new string.

• Return the new string without duplicate characters.

The minimum cost to buy and sell a product involves considering the purchase price, selling price, and any associated fees.

• Calculate the total cost by adding the purchase price and any fees incurred during the buying process.

• Calculate the total revenue by subtracting any fees incurred during the selling process from the selling price.

• Subtract the total cost from the total revenue to determine the minimum cost to buy and sell.

Trapping rainwater problem involves calculating the amount of rainwater that can be trapped between buildings.

• Calculate the maximum height of water that can be trapped at each index

• Calculate the water trapped at each index by subtracting the height of the building at that index from the minimum of the maximum heights on its left and right

• Sum up the water trapped at each index to get the total amount of rainwater trapped

Planning a drive involves determining the destination, route, mode of transportation, and necessary supplies.

• Decide on the destination and research the route

• Choose the mode of transportation (car, train, plane, etc.)

• Check for any necessary permits or visas

• Pack necessary supplies such as food, water, and clothing

• Plan for rest stops and accommodations if needed