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Author: hieu

src/bit/Problem_BitWiseANDofNumbersRange.java

@@ -9,6 +9,19 @@ public static void run() {
         System.out.println(res);
     }
 
+    /*
+    For example, for number 26 to 30
+    Their binary form are:
+
+    11010
+    11011
+    11100　　
+    11101　　
+    11110
+
+    Because we are trying to find bitwise AND, so if any bit there are at least one 0 and one 1, it always 0. In this case, it is 11000.
+    So we are go to cut all these bit that they are different. In this case we cut the right 3 bit.
+     */
     public int rangeBitwiseAnd(int m, int n) {
         int i = 0; // i means we have how many bits are 0 on the right
         while(m != n){