From afc05f02d79efedeec89266aa21ade6da13c9b65 Mon Sep 17 00:00:00 2001
From: begeekmyfriend <begeekmyfriend@gmail.com>
Date: Wed, 30 Aug 2017 10:02:09 +0800
Subject: [PATCH] Maximal rectangle

Signed-off-by: begeekmyfriend <begeekmyfriend@gmail.com>
---
 085_maximal_rectangle/Makefile            |  2 +
 085_maximal_rectangle/maximal_rectangle.c | 52 +++++++++++++++++++++++
 2 files changed, 54 insertions(+)
 create mode 100644 085_maximal_rectangle/Makefile
 create mode 100644 085_maximal_rectangle/maximal_rectangle.c

diff --git a/085_maximal_rectangle/Makefile b/085_maximal_rectangle/Makefile
new file mode 100644
index 0000000..c85beaa
--- /dev/null
+++ b/085_maximal_rectangle/Makefile
@@ -0,0 +1,2 @@
+all:
+	gcc -O2 -o test maximal_rectangle.c
diff --git a/085_maximal_rectangle/maximal_rectangle.c b/085_maximal_rectangle/maximal_rectangle.c
new file mode 100644
index 0000000..cdca77a
--- /dev/null
+++ b/085_maximal_rectangle/maximal_rectangle.c
@@ -0,0 +1,52 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <string.h>
+
+int maximalRectangle(char** matrix, int matrixRowSize, int matrixColSize) {
+    int i, j, max_area = 0;
+    for (i = 0; i < matrixRowSize; i++) {
+        for (j = 0; j < matrixColSize; j++) {
+            if (matrix[i][j] == '1') {
+                int area = 0, x, y;
+                int row = i;
+                int min_col = matrixColSize;
+                while (row < matrixRowSize) {
+                    for (x = j; x < matrixColSize && matrix[row][x] == '1'; x++) {}
+                    min_col = x < min_col ? x : min_col;
+                    area = (row - i + 1) * (min_col - j);
+                    max_area = area > max_area ? area : max_area;
+                    row++;
+                }
+                int col = j;
+                int min_row = matrixRowSize;
+                while (col < matrixColSize) {
+                    for (y = i; y < matrixRowSize && matrix[y][col] == '1'; y++) {}
+                    min_row = y < min_row ? y : min_row;
+                    area = (min_row - i) * (col - j + 1);
+                    max_area = area > max_area ? area : max_area;
+                    col++;
+                }
+            }
+        }
+    }
+    return max_area;
+}
+
+/* ./test 11111111 11111110 11111110 11111000 01111000 */
+int main(int argc, char **argv)
+{
+    if (argc < 2) {
+        fprintf(stderr, "Usage: ./test row1 row2...\n");
+        exit(-1);
+    }
+
+    int i, j;
+    int row_size = argc - 1;
+    int col_size = strlen(argv[1]);
+    for (i = 0; i < row_size; i++) {
+        printf("%s\n", argv[i + 1]);
+    }
+    printf("%d\n", maximalRectangle(argv + 1, argc - 1, strlen(argv[1])));
+    return 0;
+}