leetcode

Daily Problem

2 files changed, 29 insertions(+), 0 deletions(-)

diff --git a/ Problems/1027.cpp b/ Problems/1027.cpp

@@ -0,0 +1,28 @@

class Solution {

public:

int longestArithSeqLength(vector<int> &nums) {

unordered_map<int, vector<int>> um;

int res = 2;

for (int i = 0; i < nums.size(); i++) um[nums[i]].push_back(i);

for (const auto &[num1, vec1] : um) {

res = max(res, (int)vec1.size());

for (const auto &[num2, vec2] : um) {

if (num1 == num2) continue;

auto it = lower_bound(vec2.begin(), vec2.end(), vec1.front() + 1);

if (it == vec2.end()) continue;

int diff = num2 - num1, crnt = *it, count = 2, next;

while (true) {

if (!um.count(next = nums[crnt] + diff)) break;

auto it = lower_bound(um[next].begin(), um[next].end(), crnt + 1);

if (it == um[next].end()) break;

crnt = *it, count++;

}

res = max(res, count);

}

}

return res;

}

};

diff --git a/ README.md b/ README.md

@@ -406,6 +406,7 @@ for solving problems. | 1020 | Medium | [Number of Enclaves](Problems/1020.cpp) | | 1022 | Easy | [Sum of Root To Leaf Binary Numbers](Problems/1022.cpp) | | 1026 | Medium | [Maximum Difference Between Node and Ancestor](Problems/1026.cpp) |

| 1027 | Medium | [Longest Arithmetic Subsequence](Problems/1027.cpp) |

| 1035 | Medium | [Uncrossed Lines](Problems/1035.cpp) | | 1038 | Medium | [Binary Search Tree to Greater Sum Tree](Problems/1038.cpp) | | 1042 | Medium | [Flower Planting With No Adjacent](Problems/1042.cpp) |