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Add cpp codes for the chapter

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computational complexity, sorting, searching.
This commit is contained in:
Yudong Jin
2022-11-27 04:20:30 +08:00
parent 431a0f6caf
commit 19a4ccd86a
32 changed files with 1362 additions and 52 deletions
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7
codes/cpp/chapter_computational_complexity/leetcode_two_sum.cpp
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@ -10,6 +10,7 @@ class SolutionBruteForce {
public:
vector<int> twoSum(vector<int>& nums, int target) {
int size = nums.size();
// 两层循环，时间复杂度 O(n^2)
for (int i = 0; i < size - 1; i++) {
for (int j = i + 1; j < size; j++) {
if (nums[i] + nums[j] == target)
@ -24,7 +25,9 @@ class SolutionHashMap {
public:
vector<int> twoSum(vector<int>& nums, int target) {
int size = nums.size();
// 辅助哈希表，空间复杂度 O(n)
unordered_map<int, int> dic;
// 单层循环，时间复杂度 O(n)
for (int i = 0; i < size; i++) {
if (dic.find(target - nums[i]) != dic.end()) {
return { dic[target - nums[i]], i };
@ -45,9 +48,13 @@ int main() {
// 方法一
SolutionBruteForce* slt1 = new SolutionBruteForce();
vector<int> res = slt1->twoSum(nums, target);
cout << "方法一 res = ";
PrintUtil::printVector(res);
// 方法二
SolutionHashMap* slt2 = new SolutionHashMap();
res = slt2->twoSum(nums, target);
cout << "方法二 res = ";
PrintUtil::printVector(res);
return 0;
}