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-rw-r--r--other/max_sum_rectangle.cpp33
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;
+ }
+};