Howiezhang226

class Solution {
    public int dayOfYear(String date) {
        int[] daysOfTheMonth = new int[]{31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
        int days = 0;
        String[] split = date.split("-");
        int year = Integer.valueOf(split[0]);
        int month = Integer.valueOf(split[1]);
        int day = Integer.valueOf(split[2]);
        for (int i = 0 ; i < month - 1; i++) {
            days += daysOfTheMonth[i];

Howiezhang226

public class Solution {
    public boolean canFinish(int numCourses, int[][] prereq) {
        int[] visited = new int[numCourses];
        List<List<Integer>> courses = new ArrayList<>();
        
        for(int i=0;i<numCourses;i++){
            courses.add(new ArrayList<Integer>());
        }
        for(int i=0;i< prereq.length;i++){
            courses.get(prereq[i][1]).add(prereq[i][0]);

Howiezhang226

package c1s5;

/**
 * Created by Hao Zhang on 2015/4/9.
 *
 */
public class Solution {
    /**
     *aabbbcc => a1b3c2
     */

Howiezhang226

/*
1.4 Write a method to replace all spaces in a string with'%20'. You may assume that
the string has sufficient space at the end of the string to hold the additional
characters, and that you are given the "true" length of the string. (Note: if implementing
in Java, please use a character array so that you can perform this operation
in place.)

EXAMPLE
Input: "Mr John Smith"

Howiezhang226

import java.util.Arrays;

public class Solution {

    public String sortString(String str) {
        char[] cstr = str.toCharArray();
        Arrays.sort(cstr);
        return new String(cstr);
    }

Howiezhang226

/**
 * created by howie zhang
 * 2015/3/31
 * cc150 1.1
 */
public class Solution {
    public boolean isUnique(String s) {
        if (s.length() > 256)
            return false;
        boolean[] all = new boolean[256];