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Signed-off-by: begeekmyfriend <begeekmyfriend@gmail.com>

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0033_search_in_rotated_sorted_array
- rotated_array.cc
- rotated_array.c
0215_kth_largest_element_in_an_array
- kth_elem.c

3 files changed

+36

-26

lines changed

`‎0033_search_in_rotated_sorted_array/rotated_array.c‎`

Lines changed: 2 additions & 0 deletions

Original file line number	Diff line number	Diff line change
`@@ -12,6 +12,8 @@ static int search(int* nums, int numsSize, int target)`
`12`	`12`	`return mid;`
`13`	`13`	`}`
`14`	`14`
	`15`	`+ /* lo might be mid */`
	`16`	`+ /* We only need to consider non-rotated sorted array search */`
`15`	`17`	`if (nums[lo] <= nums[mid]) {`
`16`	`18`	`if (nums[lo] <= target && target < nums[mid]) {`
`17`	`19`	`hi = mid - 1;`

`‎0033_search_in_rotated_sorted_array/rotated_array.cc‎`

Lines changed: 5 additions & 0 deletions

Original file line number	Diff line number	Diff line change
`@@ -7,11 +7,15 @@ class Solution {`
`7`	`7`	`int search(vector<int>& nums, int target) {`
`8`	`8`	`int lo = 0;`
`9`	`9`	`int hi = nums.size() - 1;`
	`10`	`+`
`10`	`11`	`for (lo <= hi) {`
`11`	`12`	`int mid = lo + (hi - lo) / 2;`
`12`	`13`	`if (nums[mid] == target) {`
`13`	`14`	`return mid;`
`14`	`15`	`}`
	`16`	`+`
	`17`	`+ // lo might be mid`
	`18`	`+ // We only need to consider non-rotated sorted array search`
`15`	`19`	`if (nums[lo] <= nums[mid]) {`
`16`	`20`	`if (nums[lo] <= target && target < nums[mid]) {`
`17`	`21`	`hi = mid - 1;`
`@@ -26,6 +30,7 @@ class Solution {`
`26`	`30`	`}`
`27`	`31`	`}`
`28`	`32`	`}`
	`33`	`+`
`29`	`34`	`return -1;`
`30`	`35`	`}`
`31`	`36`	`};`

`‎0215_kth_largest_element_in_an_array/kth_elem.c‎`

Lines changed: 29 additions & 26 deletions

Original file line number	Diff line number	Diff line change
`@@ -1,44 +1,47 @@`
`1`	`1`	`#include <stdio.h>`
`2`	`2`	`#include <stdlib.h>`
`3`	`3`
	`4`	`+static inline void swap(int a, int b)`
	`5`	`+{`
	`6`	`+ int t = *a;`
	`7`	`+ a = b;`
	`8`	`+ *b = t;`
	`9`	`+}`
`4`	`10`
`5`		`-static int partition(int *nums, int lo, int hi)`
	`11`	`+static int quick_select(int *nums, int lo, int hi, intk)`
`6`	`12`	`{`
`7`	`13`	`if (lo >= hi) {`
`8`	`14`	`return hi;`
`9`	`15`	`}`
`10`	`16`
`11`		`- int i = lo;`
`12`		`- int j = hi;`
`13`		`- int pivot = nums[hi];`
	`17`	`+ int i = lo-1;`
	`18`	`+ int j = hi+1;`
	`19`	`+ int pivot = nums[lo];`
`14`	`20`	`while (i < j) {`
`15`		`- while (i < j && nums[i] <= pivot) { i++; }`
`16`		`- /* Loop invariant: nums[i] > pivot or i == j */`
`17`		`- nums[j] = nums[i];`
`18`		`- while (i < j && nums[j] >= pivot) { j--; }`
`19`		`- /* Loop invariant: nums[j] > pivot or i == j */`
`20`		`- nums[i] = nums[j];`
	`21`	`+ /* For case of large amounts of consecutive duplicate elements, we`
	`22`	`+ * shall make the partition in the middle of the array as far as`
	`23`	`+ * possible. If the partition is located in the head or tail, the`
	`24`	`+ * performance might well be very bad for it.`
	`25`	`+ */`
	`26`	`+ while (nums[++i] > pivot) {}`
	`27`	`+ while (nums[--j] < pivot) {}`
	`28`	`+ if (i < j) {`
	`29`	`+ swap(&nums[i], &nums[j]);`
	`30`	`+ }`
	`31`	`+ }`
	`32`	`+`
	`33`	`+ /* invariant: i == j + 1 or i == j */`
	`34`	`+ if (j >= k - 1) {`
	`35`	`+ return quick_select(nums, lo, j, k);`
	`36`	`+ } else {`
	`37`	`+ return quick_select(nums, j + 1, hi, k);`
`21`	`38`	`}`
`22`		`- /* Loop invariant: i == j */`
`23`		`- nums[i] = pivot;`
`24`		`- return i;`
`25`	`39`	`}`
`26`	`40`
`27`	`41`	`int findKthLargest(int* nums, int numsSize, int k)`
`28`	`42`	`{`
`29`		`- int lo = 0, hi = numsSize - 1;`
`30`		`- for (; ;) {`
`31`		`- int p = partition(nums, lo, hi);`
`32`		`- if (p < numsSize - k) {`
`33`		`- lo = p + 1;`
`34`		`- } else if (p > numsSize - k) {`
`35`		`- hi = p - 1;`
`36`		`- } else {`
`37`		`- lo = p;`
`38`		`- break;`
`39`		`- }`
`40`		`- }`
`41`		`- return nums[lo];`
	`43`	`+ int i = quick_select(nums, 0, numsSize - 1, k);`
	`44`	`+ return nums[i];`
`42`	`45`	`}`
`43`	`46`
`44`	`47`

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Commit d4f6d7e

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3 files changed

3 files changed

`‎0033_search_in_rotated_sorted_array/rotated_array.c‎`

`‎0033_search_in_rotated_sorted_array/rotated_array.cc‎`

`‎0215_kth_largest_element_in_an_array/kth_elem.c‎`

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