Longest Common Prefix in JAVA

Manish1Gupta · Oct 15, 2022 · 3a22526 · 3a22526
1 parent 7c9fa3e
commit 3a22526
Showing 1 changed file with 25 additions and 0 deletions.
diff --git a/Longest Common Prefix.java b/Longest Common Prefix.java
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+public String longestCommonPrefix(String[] strs) {
+    if (strs == null || strs.length == 0) return "";    
+        return longestCommonPrefix(strs, 0 , strs.length - 1);
+}
+
+private String longestCommonPrefix(String[] strs, int l, int r) {
+    if (l == r) {
+        return strs[l];
+    }
+    else {
+        int mid = (l + r)/2;
+        String lcpLeft =   longestCommonPrefix(strs, l , mid);
+        String lcpRight =  longestCommonPrefix(strs, mid + 1,r);
+        return commonPrefix(lcpLeft, lcpRight);
+   }
+}
+
+String commonPrefix(String left,String right) {
+    int min = Math.min(left.length(), right.length());       
+    for (int i = 0; i < min; i++) {
+        if ( left.charAt(i) != right.charAt(i) )
+            return left.substring(0, i);
+    }
+    return left.substring(0, min);
+}