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This commit is contained in:
Sainnhe Park
2022-11-24 16:44:36 +08:00
parent 8f3ebbdd3d
commit 2822593c46
11 changed files with 256 additions and 120 deletions
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84
src/s0034_find_first_and_last_position_of_element_in_sorted_array.cpp
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@@ -1,38 +1,66 @@
#include "s0034_find_first_and_last_position_of_element_in_sorted_array.hpp"
vector<int> Solution::searchRange(vector<int>& nums, int target) {
int size = nums.size();
if (size <= 0) {
return vector<int> {-1, -1};
} else if (size == 1) {
if (nums[0] == target) {
return vector<int> {0, 0};
// 闭区间写法
vector<int> Solution1::searchRange(vector<int>& nums, int target) {
int len = nums.size();
int l{0};
int r = len - 1;
while (l <= r) {
int m = (l + r) >> 1;
if (target < nums[m]) {
r = m - 1;
} else if (nums[m] < target) {
l = m + 1;
} else {
return vector<int> {-1, -1};
}
}
int left{0};
int right = size - 1;
int mid;
while (left <= right) {
mid = static_cast<int>(floor((left + right) / 2));
if (nums[mid] == target) {
int resultLeft, resultRight;
for (int i = mid; i < size; ++i) {
if (nums[i] == target) {
resultRight = i;
l = r = m;
while (l >= 0) {
if (nums[l] == target) {
--l;
} else {
break;
}
}
for (int i = mid; i >= 0; --i) {
if (nums[i] == target) {
resultLeft = i;
while (r <= len - 1) {
if (nums[r] == target) {
++r;
} else {
break;
}
}
return vector<int> {resultLeft, resultRight};
} else if (nums[mid] > target) {
right = mid - 1;
} else {
left = mid + 1;
return vector<int> {l + 1, r - 1};
}
}
return vector<int> {-1, -1};
}
// 开区间写法
vector<int> Solution2::searchRange(vector<int>& nums, int target) {
int len = nums.size();
int l{0};
int r = len;
while (l < r) {
int m = (l + r) >> 1;
if (target < nums[m]) {
r = m;
} else if (nums[m] < target) {
l = m + 1;
} else {
l = r = m;
while (l >= 0) {
if (nums[l] == target) {
--l;
} else {
break;
}
}
while (r <= len - 1) {
if (nums[r] == target) {
++r;
} else {
break;
}
}
return vector<int> {l + 1, r - 1};
}
}
return vector<int> {-1, -1};

58
src/s0035_search_insert_position.cpp
View File

@@ -1,33 +1,37 @@
#include "s0035_search_insert_position.hpp"
int Solution::searchInsert(vector<int>& nums, int target) {
int size = nums.size();
if (size == 0) {
return 0;
}
int left{0};
int right = size - 1;
int mid;
while (left <= right) {
mid = static_cast<int>(floor((left + right) / 2));
if (nums[mid] == target) {
return mid;
} else if (nums[mid] > target) {
right = mid - 1;
// 闭区间写法
int Solution1::searchInsert(vector<int>& nums, int target) {
int len = nums.size();
int l{0};
int r = len - 1;
while (l <= r) {
int m = (l + r) >> 1;
if (target < nums[m]) {
r = m - 1;
} else if (nums[m] < target) {
l = m + 1;
} else {
left = mid + 1;
return m;
}
}
if (right < 0) {
return 0;
} else if (left > size - 1) {
return size;
}
if (target < nums[right]) {
return right;
} else if (target > nums[left]) {
return left + 1;
} else {
return left;
}
return r + 1;
}
// 开区间写法
int Solution2::searchInsert(vector<int>& nums, int target) {
int len = nums.size();
int l{0};
int r = len;
while (l < r) {
int m = (l + r) >> 1;
if (target < nums[m]) {
r = m;
} else if (nums[m] < target) {
l = m + 1;
} else {
return m;
}
}
return r;
}

37
src/s0704_binary_search.cpp Normal file
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@@ -0,0 +1,37 @@
#include "s0704_binary_search.hpp"
// 闭区间写法
int Solution1::binSearch(vector<int>& nums, int target) {
int len = nums.size();
int l{0};
int r = len - 1;
while (l <= r) {
int m = (l + r) >> 1;
if (target < nums[m]) {
r = m - 1;
} else if (nums[m] < target) {
l = m + 1;
} else {
return m;
}
}
return -1;
}
// 开区间写法
int Solution2::binSearch(vector<int>& nums, int target) {
int len = nums.size();
int l{0};
int r = len;
while (l < r) {
int m = (l + r) >> 1;
if (target < nums[m]) {
r = m;
} else if (nums[m] < target) {
l = m + 1;
} else {
return m;
}
}
return -1;
}