ADD: leetcode solutions

Author: intfloat

leetcode/AssignCookies.java

@@ -0,0 +1,25 @@
+import java.util.Arrays;
+
+public class Solution {
+ public int findContentChildren(int[] g, int[] s) {
+ Arrays.sort(g);
+ Arrays.sort(s);
+ int pg = 0, ps = 0, res = 0;
+ while (pg < g.length && ps < s.length) {
+ if (s[ps] >= g[pg]) {
+ ++pg;
+ ++ps;
+ ++res;
+ } else {
+ ++ps;
+ }
+ }
+ return res;
+ }
+
+ public static void main(String[] args) {
+ Solution solution = new Solution();
+ System.out.println(solution.findContentChildren(new int[]{1, 2, 3}, new int[]{1, 1}));
+ System.out.println(solution.findContentChildren(new int[]{1, 2}, new int[]{1, 2, 3}));
+ }
+}

leetcode/FourSumII.java

@@ -0,0 +1,33 @@
+import java.util.HashMap;
+
+public class Solution {
+ public int fourSumCount(int[] A, int[] B, int[] C, int[] D) {
+ int n = A.length;
+ HashMap<Integer, Integer> cnt = new HashMap<>();
+ for (int i = 0; i < n; ++i) {
+ for (int j = 0; j < n; ++j) {
+ int val = A[i] + B[j];
+ if (cnt.containsKey(val)) {
+ cnt.put(val, cnt.get(val) + 1);
+ } else {
+ cnt.put(val, 1);
+ }
+ }
+ }
+ int res = 0;
+ for (int i = 0; i < n; ++i) {
+ for (int j = 0; j < n; ++j) {
+ int val = -(C[i] + D[j]);
+ if (cnt.containsKey(val)) {
+ res += cnt.get(val);
+ }
+ }
+ }
+ return res;
+ }
+
+ public static void main(String[] args) {
+ Solution solution = new Solution();
+ System.out.println(solution.fourSumCount(new int[]{1, 2}, new int[]{-2, -1}, new int[]{-1, 2}, new int[]{0, 2}));
+ }
+}

leetcode/MinimumNumberArrowBurstBallon.java

@@ -0,0 +1,29 @@
+import java.util.Arrays;
+import java.util.Comparator;
+
+public class Solution {
+ public int findMinArrowShots(int[][] points) {
+ Arrays.sort(points, new Comparator<int[]>() {
+ @Override
+ public int compare(int[] o1, int[] o2) {
+ return o1[1] - o2[1];
+ }
+ });
+ int res = 0, pv = 0;
+ for (int i = 0; i < points.length; ++i) {
+ if (i == 0 || points[i][0] > pv) {
+ ++res;
+ pv = points[i][1];
+ }
+ }
+ return res;
+ }
+
+ public static void main(String[] args) {
+ Solution solution = new Solution();
+ int[][] points = new int[][]{
+ {-2147483648,2147483647}
+ };
+ System.out.println(solution.findMinArrowShots(points));
+ }
+}

leetcode/RepeatedSubstringPattern.java

@@ -0,0 +1,27 @@
+public class Solution {
+ public boolean repeatedSubstringPattern(String str) {
+ for (int i = 1; i < str.length(); ++i) {
+ if (str.length() % i != 0) {
+ continue;
+ }
+ boolean ok = true;
+ for (int j = 0; j < str.length(); ++j) {
+ if (str.charAt(j) != str.charAt(j % i)) {
+ ok = false;
+ break;
+ }
+ }
+ if (ok) {
+ return true;
+ }
+ }
+ return false;
+ }
+
+ public static void main(String[] args) {
+ Solution solution = new Solution();
+ System.out.println(solution.repeatedSubstringPattern("abab"));
+ System.out.println(solution.repeatedSubstringPattern("aba"));
+ System.out.println(solution.repeatedSubstringPattern("abcabcabcabc"));
+ }
+}