Commit 5b27a31

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C5141506

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Leetcode problems

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src/main/problems/java_problem/dynamic_programming
- EggBreaks.java
- StringPermutation.java

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	`1`	`+package java_problem.dynamic_programming;`
	`2`	`+`
	`3`	`+public class EggBreaks {`
	`4`	`+ public static void main(String[] args) {`
	`5`	`+ System.out.println(twoEggDrop(7));`
	`6`	`+ }`
	`7`	`+`
	`8`	`+ public static int twoEggDrop(int floor) {`
	`9`	`+ int egg = 2; // hard coded to 2 eggs for this problem`
	`10`	`+ int[][] dp = new int[floor + 1][egg + 1];`
	`11`	`+ return eggDrop(floor, egg, dp);`
	`12`	`+ }`
	`13`	`+`
	`14`	`+ public static int eggDrop(int floor, int egg, int[][] dp) {`
	`15`	`+ if (floor <= 2 \|\| egg == 1) return floor;`
	`16`	`+ if (dp[floor][egg] != 0) return dp[floor][egg];`
	`17`	`+ int min = floor; // when you drop at each floor starting from 1`
	`18`	`+ for (int flr = 1; flr < floor; flr++) {`
	`19`	`+ int eggBreak = 1 + eggDrop(flr - 1, egg - 1, dp); // drops needed if egg breaks at this floor`
	`20`	`+ int noEggBreak = 1 + eggDrop(floor - flr, egg, dp); // drops needed if egg does not break at this floor`
	`21`	`+ int moves = Math.max(eggBreak, noEggBreak); // since we want certain moves for floor floor take max`
	`22`	`+ min = Math.min(min, moves);`
	`23`	`+ }`
	`24`	`+ dp[floor][egg] = min;`
	`25`	`+ return min;`
	`26`	`+ }`
	`27`	`+}`

Lines changed: 41 additions & 0 deletions

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	`1`	`+package java_problem.dynamic_programming;`
	`2`	`+`
	`3`	`+import java.util.ArrayList;`
	`4`	`+import java.util.List;`
	`5`	`+`
	`6`	`+public class StringPermutation {`
	`7`	`+ public static void main(String[] args) {`
	`8`	`+ System.out.println(checkInclusion("ab", "eidbaooo"));`
	`9`	`+ }`
	`10`	`+`
	`11`	`+ //return true if s2 contains permutation of s1`
	`12`	`+ public static boolean checkInclusion(String s1, String s2) {`
	`13`	`+ int n2 = s2.length();`
	`14`	`+ int totalPermutation = fact(n2);`
	`15`	`+ List<String> permutations = findPermutation(totalPermutation, s2);`
	`16`	`+ return permutations.contains(s1);`
	`17`	`+ }`
	`18`	`+`
	`19`	`+ public static List<String> findPermutation(int totalPermutation, String s) {`
	`20`	`+ List<String> permutations = new ArrayList<>();`
	`21`	`+ for (int i = 0; i < totalPermutation; i++) {`
	`22`	`+ StringBuilder sb = new StringBuilder(s);`
	`23`	`+ int dividend = i;`
	`24`	`+ StringBuilder permutation = new StringBuilder();`
	`25`	`+ for (int divisor = s.length(); divisor >= 1; divisor--) {`
	`26`	`+ int q = dividend / divisor;`
	`27`	`+ int r = dividend % divisor;`
	`28`	`+ permutation.append(sb.charAt(r));`
	`29`	`+ sb.deleteCharAt(r);`
	`30`	`+ dividend = q;`
	`31`	`+ }`
	`32`	`+ permutations.add(String.valueOf(permutation));`
	`33`	`+ }`
	`34`	`+ return permutations;`
	`35`	`+ }`
	`36`	`+`
	`37`	`+ public static int fact(int n) {`
	`38`	`+ if (n == 1) return n;`
	`39`	`+ return n * fact(n - 1);`
	`40`	`+ }`
	`41`	`+}`

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