tiagopereira17’s gists

tiagopereira17 / MissingInteger.java

Created June 28, 2016 14:37

Find the minimal positive integer not occurring in a given sequence.

	public class MissingInteger {
	public int minMissingInteger(int[] A) {
	if(A == null \|\| A.length == 0) {
	return -1;
	}

	int[] items = new int[A.length + 1];
	for(int i = 0; i < items.length; i++) {
	items[i] = -1;
	}

tiagopereira17 / PermCheck.java

Created June 25, 2016 17:37

Check whether array A is a permutation.

	public class PermCheck {
	public int checkIfIsPermutation(int[] A) {
	if(A == null \|\| A.length == 0) {
	return -1;
	}

	int[] passed = new int[A.length];
	for(int i = 0; i < passed.length; i++) {
	passed[i] = -1;
	}

tiagopereira17 / FrogRiverOne.java

Created June 25, 2016 17:00

Find the earliest time when a frog can jump to the other side of a river.

	public class FrogRiverOne {
	public int solution(int X, int[] A) {
	if(A == null \|\| A.length == 0) {
	return -1;
	}

	int[] passed = new int[X];
	for(int i = 1; i <= passed.length; i++) {
	passed[i-1] = -1;
	}

tiagopereira17 / PermMissingElem.java

Last active July 19, 2023 12:43

Find the missing element in a given permutation.

	public class PermMissingElem {

	public int findMissingElement(int[] A) {
	if(A == null \|\| A.length == 0) {
	return 1;
	}

	long N = A.length + 1;
	long total = N * (N + 1) / 2;

tiagopereira17 / TapeEquilibrium.java

Created June 22, 2016 01:59

Minimize the value |(A[0] + ... + A[P-1]) - (A[P] + ... + A[N-1])|.

	public class TapeEquilibrium {

	public int solution(int[] A) {
	int start = A[0];
	int end = sum(A) - start;
	int minDif = Math.abs(start - end);

	for(int i = 1; i < A.length - 1; i++) {
	start += A[i];
	end -= A[i];

tiagopereira17 / FrogJump.java

Last active June 22, 2016 01:20

The frog is located at position X and wants to get to a position greater than or equal to Y. The frog always jumps a fixed distance, D. Count the minimal number of jumps that the frog must perform to reach its target.

	public class FrogJump {
	public int countJumps(int X, int Y, int D) {
	if(X > Y) {
	return 0;
	}

	return (int) Math.ceil((Y - X) / (double) D);
	}
	}

tiagopereira17 / OddOccurrencesInArray.java

Created June 22, 2016 00:42

A non-empty zero-indexed array A consisting of N integers is given. The array contains an odd number of elements, and each element of the array can be paired with another element that has the same value, except for one element that is left unpaired.

	public class OddOccurrencesInArray {
	public int solution(int[] A) {
	if(A == null \|\| A.length == 0) {
	return 0;
	}

	if(A.length == 1) {
	return A[0];
	}

tiagopereira17 / CyclicRotation.java

Last active June 22, 2016 00:09

Rotate the array A, K times. Each element of A will be shifted to the right by K indexes.

	public class CyclicRotation {

	public int[] rotate(int[] A, int K) {
	if(A == null \|\| A.length == 0) {
	return new int[0];
	}

	int length = A.length;

	if(K > length) {

tiagopereira17 / BinaryGap.java

Last active June 22, 2016 02:03

Find the longest sequence of zeros in binary representation of an integer.

	public class BinaryGap {

	public int solution(int N) {
	int max = 0;
	int counter = 0;
	boolean isCounting = false;

	while(N > 0) {
	if((N & 1) == 1) {
	if(isCounting) {

Tiago Pereira tiagopereira17