class Solution {
public void duplicateZeros(int[] arr) {
ArrayList rem = new ArrayList();
for (int i = 0; i < arr.length; i++) {
if (arr[i] == 0) {
rem.add(0);
rem.add(0);
arr[i] = rem.get(0);
rem.remove(0);
}else {
rem.add(arr[i]);
arr[i] = rem.get(0);
rem.remove(0);
}
}
}
}
329. Longest Increasing Path in a Matrix
class Solution {
public int longestIncreasingPath(int[][] matrix) {
if (matrix.length == 0) return 0;
int max = Integer.MIN_VALUE;
int [][] mem = new int[matrix.length][matrix[0].length];
for (int i = 0; i < matrix.length; i++)
Arrays.fill(mem[i], 0);
for (int i = 0; i < matrix.length; i++) {
for (int j = 0; j < matrix[i].length; j++) {
max = Math.max(max,helper(i, j, mem,matrix));
}
}
return max;
}
public int helper(int x, int y, int[][] mem, int[][] matrix) {
if (mem[x][y] != 0) {
return mem[x][y];
}
int[] dx = { 0, 1, -1, 0 };
int[] dy = { 1, 0, 0, -1 };
for (int i = 0; i = 0 && newX = 0 && newY matrix[x][y]) {
mem[x][y] = Math.max(mem[x][y], helper(newX, newY,mem, matrix));
}
}
return ++mem[x][y];
}
}
class Solution {
public int[] relativeSortArray(int[] arr1, int[] arr2) {
HashMap h = new HashMap();
for (int i = 0; i < arr2.length; i++) {
h.put(i, arr2[i]);
}
// queue to keep the new list in ascending order
PriorityQueue rem = new PriorityQueue();
int existing = 0;
for (int i = 0; i < arr1.length; i++) {
if (null != getKeyFromValue(h, arr1[i])) {
arr1[i] = getKeyFromValue(h, arr1[i]);
existing++;
} else {
rem.add(arr1[i]);
arr1[i] = Integer.MAX_VALUE;
}
}
Arrays.sort(arr1);
for (int i = 0; i < existing; i++) {
arr1[i] = h.get(arr1[i]);
}
for (int i = existing; i < arr1.length; i++) {
arr1[i] = rem.poll();
}
return arr1;
}
public static Integer getKeyFromValue(HashMap hm, int value) {
for (Integer o : hm.keySet()) {
if (((Integer) hm.get(o)).intValue() == value) {
return o;
}
}
return null;
}
}
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
class Solution {
public String dayOfTheWeek(int day, int month, int year) {
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
Date date = null;
try {
date = format.parse(year + "-" + ((month <= 9) ? ("0" + month) : ("" + month)) + "-" + ((day <= 9) ? ("0" + day) : ("" + day)));
} catch (ParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
int d = date.getDay();
String dayString = null;
switch (d) {
case 1:
dayString = "Monday";
break;
case 2:
dayString = "Tuesday";
break;
case 3:
dayString = "Wednesday";
break;
case 4:
dayString = "Thursday";
break;
case 5:
dayString = "Friday";
break;
case 6:
dayString = "Saturday";
break;
case 0:
dayString = "Sunday";
break;
default:
dayString = "Invalid day";
break;
}
return dayString;
}
}
1160. Find Words That Can Be Formed by Characters
class Solution {
public int countCharacters(String[] words, String chars) {
HashMap freq = new HashMap();
for (int i = 0; i < chars.length(); i++) {
freq.put(chars.charAt(i), freq.getOrDefault(chars.charAt(i), 0) + 1);
}
int count = 0;
for (int i = 0; i < words.length; i++) {
HashMap freq1 = new HashMap(freq);
boolean charsNotFound = false;
for (int j = 0; j 0)
freq1.put(words[i].charAt(j), freq1.get(words[i].charAt(j)) - 1);
else {
charsNotFound = true;
break;
}
}
if (!charsNotFound)
count += words[i].length();
}
return count;
}
}
class Solution {
public String defangIPaddr(String address) {
return address.replace(".","[.]");
}
}
class Solution {
public int heightChecker(int[] heights) {
int[] original = new int[heights.length];
original = heights.clone();
Arrays.sort(heights);
int count = 0;
for (int i = 0; i < heights.length; i++) {
if (heights[i] != original[i])count++;
}
return count;
}
}
class Solution {
public int strStr(String haystack, String needle) {
if (needle.equals("")) return 0;
if (haystack.equals("")) return -1;
for (int i = 0; i < haystack.length();){
int temp = i;
int neadleIndex= 0;
while(i < haystack.length() &&
neadleIndex < needle.length() &&
haystack.charAt(i) ==needle.charAt(neadleIndex)){
neadleIndex++;
i++;
}
if(neadleIndex-1 == needle.length() -1) return temp;
else {
i = temp+1 ;
}
}
return -1;
}
}
class Solution {
public int romanToInt(String s) {
int out = 0;
for (int i = 0; i <s>= 0 && s.charAt(i-1) == 'I'){
out -= 1;
out += 4;
}else out += 5;
}
//3
else if (s.charAt(i) == 'X'){
if ((i-1) >= 0 && s.charAt(i-1) == 'I'){
out -= 1;
out += 9;
}else out += 10;
}
//4
else if (s.charAt(i) == 'L'){
if ((i-1) >= 0 && s.charAt(i-1) == 'X'){
out -= 10;
out += 40;
}else out += 50;
}
//5
else if (s.charAt(i) == 'C'){
if ((i-1) >= 0 && s.charAt(i-1) == 'X'){
out -= 10;
out += 90;
}else out += 100;
}
//6
else if (s.charAt(i) == 'D'){
if ((i-1) >= 0 && s.charAt(i-1) == 'C'){
out -= 100;
out += 400;
}else out += 500;
}
//7
else if (s.charAt(i) == 'M'){
if ((i-1) >= 0 && s.charAt(i-1) == 'C'){
out -= 100;
out += 900;
}else out += 1000;
}
}
return out;
}
}
class Solution {
public boolean isPalindrome(int x) {
if( x < 0 ) // negative
return false;
String nm = String.valueOf(x);
int start = 0;
int end = nm.length() -1;
while(start <= end){
if(nm.charAt(start) != nm.charAt(end)) return false;
start++;
end--;
}
return true;
}
}
