diff options
Diffstat (limited to 'other/max_sum_rectangle.cpp')
-rw-r--r-- | other/max_sum_rectangle.cpp | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/other/max_sum_rectangle.cpp b/other/max_sum_rectangle.cpp new file mode 100644 index 0000000..9b252e1 --- /dev/null +++ b/other/max_sum_rectangle.cpp @@ -0,0 +1,33 @@ +#include "leetcode.h" + +class Solution { +public: + int maxSumSubmatrix(vector<vector<int>> &matrix, int k) { + int ans = INT_MIN, rows = matrix.size(), cols = matrix[0].size(); + for (int l = 0; l < cols; ++l) { + vector<int> sums(rows); + for (int r = l; r < cols; ++r) { + int pMin = 0, pMax = INT_MIN; + for (int i = 0; i < rows; ++i) { + sums[i] += matrix[i][r]; + pMin = max(pMin + sums[i], sums[i]); + pMax = max(pMax, pMin); + } + if (pMax <= k) { + ans = max(ans, pMax); + continue; + } + set<int> s = {0}; + int runSum = 0; + for (int sum : sums) { + runSum += sum; + auto it = s.lower_bound(runSum - k); + if (it != end(s)) + ans = max(ans, runSum - *it); + s.insert(runSum); + } + } + } + return ans; + } +}; |