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Diffstat (limited to 'other/longest_arithmetic_subseq_diff.cpp')
-rw-r--r-- | other/longest_arithmetic_subseq_diff.cpp | 33 |
1 files changed, 0 insertions, 33 deletions
diff --git a/other/longest_arithmetic_subseq_diff.cpp b/other/longest_arithmetic_subseq_diff.cpp deleted file mode 100644 index dc6e9ff..0000000 --- a/other/longest_arithmetic_subseq_diff.cpp +++ /dev/null @@ -1,33 +0,0 @@ -// 1218. Longest Arithmetic Subsequence of Given Difference -#include "leetcode.h" - -/* - * given an integer array 'arr' and an integer 'difference', return the length - * of the longest subsequence in 'arr' which is an arithmetic sequence such that - * the difference between adjacent elements in the subsequence equals - * 'difference'. a subsequence is a sequence that can be derived from 'arr' by - * deleting some or no elements without changing the order of the remaining - * elements. - */ - -class Solution { -public: - int longestSubsequence(vector<int> &arr, int difference) { - int ans = 1; - unordered_map<int, int> max; - for (int i = 0; i < arr.size(); i++) - max[arr[i]] = max[arr[i] - difference] + 1; - for (auto i : max) - ans = std::max(ans, i.second); - return ans; - } -}; - -int main() { - Solution obj; - vector<int> a1 = {1, 2, 3, 4}, a2 = {1, 3, 5, 7}, - a3 = {1, 5, 7, 8, 5, 3, 4, 2, 1}; - printf("%d\n", obj.longestSubsequence(a1, 1)); // expect: 4 - printf("%d\n", obj.longestSubsequence(a2, 1)); // expect: 1 - printf("%d\n", obj.longestSubsequence(a3, -2)); // expect: 4 -} |