solved 2 problems.

Author: coderfive

072.Edit Distance/coderfive/72.cc

@@ -0,0 +1,60 @@
+#include <vector>
+#include <string>
+#include <utility>
+#include <iostream>
+#include <algorithm>
+#include <limits>
+#include <numeric>
+using namespace std;
+
+class Solution {
+    public:
+	int minDistance(string word1, string word2) {
+	    vector<int> v;
+	    for (int i = 0; i <= word1.size(); i++)
+		v.push_back(i);
+	    for (int j = 0; j < word2.size(); j++) {
+		int t = v[0];
+		v[0] = j+1;
+		for (int i = 0; i < word1.size(); i++) {
+		    int cost;
+		    if (word2[j] == word1[i])
+			cost = t;
+		    else 
+			cost = min(t, min(v[i], v[i+1]))+1;
+		    t = v[i+1];
+		    v[i+1] = cost;
+		}
+	    }
+	    return v.back();
+	}
+};
+
+bool err = false;
+void do_test (const string& s1, const string& s2, int expected) {
+    static int counter = 0;
+    counter++;
+    string ns1(s1), ns2(s2);
+    int ret = Solution().minDistance(ns1, ns2);
+    if (ret != expected) {
+	err = true;
+	cout << "#" << counter << "\n"
+	    << "input: '" << s1 << "', '" << s2 << "'\n"
+	    << "expected: " << expected << "\n"
+	    << "ret: " << ret << "\n\n";
+    }
+}
+
+int main() {
+    do_test ("", "", 0);
+    do_test ("a", "", 1);
+    do_test ("", "a", 1);
+    do_test ("a", "b", 1);
+    do_test ("ab", "b", 1);
+    do_test ("ba", "b", 1);
+
+    if (!err)
+        cout << "All tests passed!\n";
+
+    return 0;
+}

085.Maximal Rectangle/coderfive/85.cc

@@ -0,0 +1,84 @@
+#include <vector>
+#include <string>
+#include <utility>
+#include <iostream>
+#include <algorithm>
+#include <limits>
+#include <numeric>
+using namespace std;
+
+template<typename T>
+ostream& operator << (ostream& out, const vector<T>& vi) {
+    out << "{";
+    if (vi.size() != 0)
+        out << vi[0];
+    for (int i = 1; i < vi.size(); i++)
+        out << ", " << vi[i];
+    out << "}";
+    return out;
+}
+
+bool err = false;
+
+class Solution {
+    public:
+	int maximalRectangle(vector<vector<char>>& matrix) {
+	    if (matrix.size() == 0 || matrix[0].size() == 0) return 0;
+	    int rows = matrix.size(), sz = matrix[0].size();
+	    int res = 0;
+	    vector<int> ht(sz, 0), stack;
+	    stack.reserve(sz);
+	    for (int i = 0; i < rows; i++) {
+		for (int j = 0; j < sz; j++) {
+		    if (matrix[i][j] == '0')
+			ht[j] = 0;
+		    else
+			ht[j]++;
+		    while (stack.size() > 0 && ht[stack.back()] > ht[j]) {
+			int left, height = ht[stack.back()];
+			stack.pop_back();
+			if (stack.size() == 0)
+			    left = -1;
+			else
+			    left = stack.back();
+			int area = height * (j-left-1);
+			if (area > res) res = area;
+		    }
+		    stack.push_back(j);
+		}
+		while (stack.size() > 0) {
+		    int left, height = ht[stack.back()];
+		    stack.pop_back();
+		    if (stack.size() == 0)
+			left = -1;
+		    else
+			left = stack.back();
+		    int area = height * (sz-left-1);
+		    if (area > res) res = area;
+		}
+	    }
+	    return res;
+	}
+};
+
+void do_test (const vector<vector<char>>& h, int res) {
+    vector<vector<char>> copy(h);
+    int ret = Solution().maximalRectangle(copy);
+    if (ret != res) {
+	err = true;
+	cout << "input: " << copy << "\n"
+	    << "result: " << ret << ", expected: " << res << "\n\n";
+    }
+}
+
+int main() {
+    do_test ({{'1'}}, 1);
+    do_test ({{'0','1','1','0'},{'1','1','1','1'}}, 4);
+    do_test ({{'0','1','1','0'},{'1','1','1','0'}}, 4);
+    do_test ({{'0','1','1','1'},{'1','1','1','1'}}, 6);
+    do_test ({{'0','0','1','0'},{'1','1','1','1'}}, 4);
+    if (!err)
+	cout << "All tests passed!\n";
+
+    return 0;
+}