-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathLeetCode.java
More file actions
176 lines (136 loc) · 4.82 KB
/
LeetCode.java
File metadata and controls
176 lines (136 loc) · 4.82 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
package com.cpoletti;
import java.lang.reflect.Array;
import java.util.*;
import java.util.stream.Collectors;
import java.util.stream.IntStream;
import java.util.stream.Stream;
public class LeetCode {
//Two Sum
public int[] twoSum(int[] nums, int target) {
int size = nums.length;
for (int principalIndex = 0; principalIndex < size; principalIndex++) {
int firstValue = nums[principalIndex];
for (int secondaryIndex = principalIndex + 1; secondaryIndex < size; secondaryIndex++) {
int secondValue = nums[secondaryIndex];
if ((firstValue + secondValue) == target)
return new int[]{principalIndex, secondaryIndex};
}
}
return new int[0];
}
//Two Sum
public int[] twoSumV2(int[] nums, int target) {
Map<Integer, Integer> map = new HashMap<Integer, Integer>();
for (int i = 0; i < nums.length; i++) {
map.put(nums[i], i);
}
int[] result = new int[2];
for (int i = 0; i < nums.length; i++) {
int remain = target - nums[i];
if (map.containsKey(remain)) {
int ri = map.get(remain);
if (i != ri) {
result[0] = i;
result[1] = ri;
break;
}
}
}
return result;
}
//Add Two Numbers
public ListNode addTwoNumbers(ListNode l1, ListNode l2) {
int carry = 0;
int sum = 0;
ListNode result = new ListNode();
ListNode current = result;
while (l1 != null || l2 != null) {
int v1 = 0;
int v2 = 0;
if (l1 != null) {
v1 = l1.val;
l1 = l1.next;
}
if (l2 != null) {
v2 = l2.val;
l2 = l2.next;
}
sum = v1 + v2 + carry;
carry = sum / 10;
sum = sum % 10;
current.next = new ListNode(sum);
current = current.next;
}
if (carry == 1) {
current.next = new ListNode(carry);
}
return result.next;
}
//Longest Substring Without Repeating Characters
public int lengthOfLongestSubstring(String s) {
int left = 0, right = 0, max = 0;
Set<Character> set = new HashSet<>();
while (right < s.length()) {
if (!set.contains(s.charAt(right))) {
set.add(s.charAt(right++));
max = Math.max(max, set.size());
//System.out.println("N:" + set);
} else {
set.remove(s.charAt(left++));
//System.out.println("S:" + set);
}
}
return max;
}
public double findMedianSortedArrays(int[] nums1, int[] nums2) {
int[] sortedList = IntStream.concat(Arrays.stream(nums1), Arrays.stream(nums2)).sorted().toArray();
int size = sortedList.length;
int middle = size / 2;
double med = 0;
if (size % 2 == 0) {
med = ((double) sortedList[middle] + (double) sortedList[middle - 1]) / 2;
} else {
med = (double) sortedList[middle];
}
return med;
}
public double findMedianSortedArraysV2(int[] nums1, int[] nums2) {
int total = nums1.length + nums2.length;
int half = total / 2;
int[] minor = nums1;
int[] major = nums2;
if (nums1.length > nums2.length){
minor = nums2;
major = nums1;
}
int left = 0;
int right = minor.length - 1;
while (true){
if ((right < 0) && ((left + right) % 2 != 0)) {
right = right-1;
}
int indexMinor = (left + right) / 2;
int indexMajor = half - indexMinor - 2;
double minorLeft = Double.MAX_VALUE * -1;
double minorRight = Double.MAX_VALUE;
double majorLeft = Double.MAX_VALUE * -1;
double majorRight = Double.MAX_VALUE;
if (indexMinor >= 0) minorLeft = minor[indexMinor];
if ((indexMinor + 1) < minor.length) minorRight = minor[indexMinor + 1];
if (indexMajor >= 0) majorLeft = major[indexMajor];
if ((indexMajor + 1) < major.length) majorRight = major[indexMajor + 1];
if ((minorLeft <= majorRight) && (majorLeft <= minorRight)){
if (total % 2 != 0){
return Math.min(minorRight, majorRight);
}else{
return (Math.max(minorLeft, majorLeft) + Math.min(minorRight, majorRight))/2;
}
}
if (minorLeft > majorRight){
right = indexMinor - 1;
}else{
left = indexMinor + 1;
}
}
}
}