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Commit 0b681a0

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735 solved. (#67)
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‎README.md

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### Stack
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* [155. Min Stack](src/0155_min_stack/min_stack.go)
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* [735. Asteroid Collision](src/0735_asteroid_collision/ac.go)
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### String
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* [3. Longest Substring Without Repeating Characters](./src/0003_longest_substring_without_repeating_characters/longest_substring_without_repeating_characters.go)   *`sliding window;`*  *`hash table`*

‎src/0735_asteroid_collision/ac.go

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/*
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735. Asteroid Collision
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https://leetcode.com/problems/asteroid-collision/
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We are given an array asteroids of integers representing asteroids in a row.
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For each asteroid, the absolute value represents its size,
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and the sign represents its direction (positive meaning right, negative meaning left).
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Each asteroid moves at the same speed.
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Find out the state of the asteroids after all collisions.
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If two asteroids meet, the smaller one will explode. If both are the same size, both will explode.
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Two asteroids moving in the same direction will never meet.
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Note:
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The length of asteroids will be at most 10000.
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Each asteroid will be a non-zero integer in the range [-1000, 1000]..
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*/
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// time: 2019年01月14日
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package ac
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// stack
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// time complexity: O(N), where NN is the number of asteroids. Our stack pushes and pops each asteroid at most once.
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// space complexity: O(N), the size of stack.
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func asteroidCollision(asteroids []int) []int {
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stack := make([]int, 0)
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for _, asteroid := range asteroids {
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flag := true
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for len(stack) > 0 && asteroid < 0 && stack[len(stack)-1] > 0 {
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if stack[len(stack)-1] == -asteroid {
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stack = stack[:len(stack)-1]
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} else if stack[len(stack)-1] < -asteroid {
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stack = stack[:len(stack)-1]
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continue
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}
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flag = false
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break
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}
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if flag {
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stack = append(stack, asteroid)
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}
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}
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return stack
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}

‎src/0735_asteroid_collision/ac_test.go

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package ac
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import (
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"reflect"
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"testing"
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)
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func TestAsteroidCollision(t *testing.T) {
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testCases := [][]int{
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{5, 10, -5},
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{-2, 2, -1, -2},
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{-2, -1, 1, 2},
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{8, -8},
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{10, 2, -5},
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}
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expected := [][]int{
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{5, 10},
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{-2},
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{-2, -1, 1, 2},
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{},
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{10},
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}
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for index, asteroids := range testCases {
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if res := asteroidCollision(asteroids); !reflect.DeepEqual(res, expected[index]) {
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t.Errorf("expected %v, got %v", expected[index], res)
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}
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}
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}

‎src/README.md

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|0713|[713. Subarray Product Less Than K](0713_subarray_product_less_than_k/spltk.go)|Medium|*`sliding window`*|
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|0717|[717. 1-bit and 2-bit Characters](0717_1_bit_and_2_bit_characters/1bitand2bitc.go)|Easy||
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|0728|[Self Dividing Numbers](./0728_self_dividing_numbers/self_dividing_numbers.go)|Easy||
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|0735|[735. Asteroid Collision](0735_asteroid_collision/ac.go)|Medium|*`stack`*|
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|0747|[Largest Number At Least Twice of Others](./0747_largest_number_at_least_twice_of_others/largest_number_at_least_twice_of_others.go)|Easy||
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|0872|[872. Leaf-Similar Trees](0872_leaf_similar_trees/leaf_similar_trees.go)|Easy|*`binary tree`*|

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