minimum_window_substring

Author: hitzzc

README.md

@@ -65,6 +65,7 @@ Golang solution for leetcode. For each problem, there is a simple *_test.go to t
 #### [73. set matrix zeroes](https://github.com/hitzzc/go-leetcode/tree/master/set_matrix_zeroes)
 #### [74. search a 2D matrix](https://github.com/hitzzc/go-leetcode/tree/master/search_a_2D_matrix)
 #### [75. sort colors](https://github.com/hitzzc/go-leetcode/tree/master/sort_colors)
+#### [76. minimum window substring](https://github.com/hitzzc/go-leetcode/tree/master/minimum_window_substring)
 
 
 

minimum_window_substring/minimum_window_substring.go

@@ -0,0 +1,45 @@
+package minimum_window_substring
+
+func minWindow(s string, t string) string {
+	sBytes, tBytes := []byte(s), []byte(t)
+	if len(sBytes) == 0 || len(tBytes) == 0 || len(sBytes) < len(tBytes) {
+		return ""
+	}
+	sMap := map[byte]int{}
+	tMap := map[byte]int{}
+	for _, b := range tBytes {
+		tMap[b]++
+	}
+	begin, tmpBegin := 0, 0
+	minSize := -1
+	letters := 0
+	for i := 0; i < len(sBytes); i++ {
+		b := sBytes[i]
+		sMap[b]++
+		if _, ok := tMap[b]; ok && sMap[b] < tMap[b] {
+			letters++
+		}
+		if letters == len(tBytes) {
+			for tmpBegin < i {
+				if _, ok := tMap[sBytes[tmpBegin]]; ok {
+					if sMap[sBytes[tmpBegin]] == tMap[sBytes[tmpBegin]] {
+						break
+					}
+					sMap[sBytes[tmpBegin]]--
+				}
+				tmpBegin++
+			}
+			if minSize == -1 || i-tmpBegin < minSize {
+				minSize = i - tmpBegin
+				begin = tmpBegin
+			}
+		}
+		letters--
+		tmpBegin++
+		sMap[sBytes[tmpBegin]]--
+	}
+	if minSize == -1 {
+		return ""
+	}
+	return s[begin : begin+minSize+1]
+}