751. IP to CIDR

Author: gzc

cpp/751-760/IP to CIDR.cpp

@@ -33,7 +33,7 @@ class Solution {
         vector<string> ans;
 
         while (n > 0) {
-            long rightMost = start & -start;
+            long rightMost = start == 0 ? 1 << 30 : start & -start;
             while (rightMost > n) rightMost /= 2;
             ans.push_back(construct(start, rightMost));
             n -= rightMost;