Merge pull request #1 from lliuquan/lliuquan-patch-1

lliuquan · web-flow · commit 567096499e1e · 2018-11-28T22:01:19.000+08:00
Create Whits.md
diff --git a/2019.11.24/Whits.md b/2019.11.24/Whits.md
@@ -0,0 +1,58 @@
+package AC;
+
+import java.lang.reflect.Array;
+
+public class leetcode_28_AC {
+
+    
+    
+    public static void main(String[] args) {
+
+        String haystack = "hello";
+        String needle = "ll";
+        System.out.println(strStrNew(haystack,needle));
+
+    }
+    public static int strStr(String haystack, String needle) {
+        if (needle.length()==0)
+            return 0;
+        char[]hayStackCharArray =haystack.toCharArray();
+        char[]needleCharArray = needle.toCharArray();
+        for (int i = 0; i < hayStackCharArray.length; i++) {
+            if (hayStackCharArray[i] == needleCharArray[0]) {   //第一个指针对比，若相同则进入if语句。
+                int j = i+1;        //把此时的i+1赋值给k，直接比较第二个值
+                int k = 1;          //直接比较第二个值
+                for (; k<needleCharArray.length && j<hayStackCharArray.length; k++) {
+                   if (hayStackCharArray[j] == needleCharArray[k])
+                    j++;
+                   else {
+                       break;
+                   }
+                }
+                if (needleCharArray.length==k){
+                    return i;
+                }
+            }
+        }
+        return -1;
+    }
+
+    public static int strStrNew(String haystack, String needle){
+       int hayStackLength  = haystack.length();
+       int needleLength = needle.length();
+       if (needleLength>hayStackLength) return -1; if (needleLength == 0) return 0;
+        for (int i = 0; i<hayStackLength-needleLength;i++) {
+            if (haystack.substring(i,needleLength+i).equals(needle))
+                return i;
+        }
+        return -1;
+    }
+    /**
+    * 还应该尝试下kmp算法
+    * @author：liuquan
+    * @date：2018/11/28 22:00
+    * @param 
+    * @return 
+    */
+    
+}
