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Given array of integers, find the sum of absolute differences of consecutive numbers.

Example

For inputArray = [4, 7, 1, 2], the output should be
arraySumAdjacentDifference(inputArray) = 10.

• |4 - 7| = 3;
• |7 - 1| = 6;
• |1 - 2| = 1

So, the answer is 3 + 6 + 1 = 10.

Input/Output

• [execution time limit] 3 seconds (java)

• [input] array.integer inputArray

  Guaranteed constraints:
  3 ≤ inputArray.length ≤ 10,
  1 ≤ inputArray[i] ≤ 15.

• [output] integer

  • Sum of absolute differences of consecutive numbers from inputArray.

[Java] Syntax Tips

// Prints help message to the console
// Returns a string
// 
// Globals declared here will cause a compilation error,
// declare variables inside the function instead!
String helloWorld(String name) {
    System.out.println("This prints to the console when you Run Tests");
    return "Hello, " + name;
}

Given an integer, find the sum of all its digits.

Example

For n = 111, the output should be digitSum(n) = 3.

1 + 1 + 1 = 3.

Input/Output

• [execution time limit] 3 seconds (java)

• [input] integer n

  Guaranteed constraints:
  0 ≤ n ≤ 2 · 109.

• [output] integer

[Java] Syntax Tips

// Prints help message to the console
// Returns a string
// 
// Globals declared here will cause a compilation error,
// declare variables inside the function instead!
String helloWorld(String name) {
    System.out.println("This prints to the console when you Run Tests");
    return "Hello, " + name;
}

Given an array a that contains only numbers in the range from 1 to a.length, find the first duplicate number for which the second occurrence has the minimal index. In other words, if there are more than 1 duplicated numbers, return the number for which the second occurrence has a smaller index than the second occurrence of the other number does. If there are no such elements, return -1.

Example

• For a = [2, 1, 3, 5, 3, 2], the output should be firstDuplicate(a) = 3.

  There are 2 duplicates: numbers 2 and 3. The second occurrence of 3 has a smaller index than the second occurrence of 2 does, so the answer is 3.

• For a = [2, 2], the output should be firstDuplicate(a) = 2;

• For a = [2, 4, 3, 5, 1], the output should be firstDuplicate(a) = -1.

Input/Output

• [execution time limit] 3 seconds (java)

• [input] array.integer a

  Guaranteed constraints:
  1 ≤ a.length ≤ 105,
  1 ≤ a[i] ≤ a.length.

• [output] integer

  • The element in a that occurs in the array more than once and has the minimal index for its second occurrence. If there are no such elements, return -1.

[Java] Syntax Tips

// Prints help message to the console
// Returns a string
// 
// Globals declared here will cause a compilation error,
// declare variables inside the function instead!
String helloWorld(String name) {
    System.out.println("This prints to the console when you Run Tests");
    return "Hello, " + name;
}