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Author: assassint2017

Implement Rand10() Using Rand7()/Implement_Rand10()_Using_Rand7().cpp

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+// The rand7() API is already defined for you.
+// int rand7();
+// @return a random integer in the range 1 to 7
+
+class Solution 
+{
+public:
+    int rand10() 
+    {
+        while (true)
+        {
+            int bit1 = rand7();
+            int bit2 = rand7();
+
+            int res = (bit1 - 1) * 7 + bit2;
+
+            if (1 <= res && res <= 40)
+                return res % 10 + 1;
+        }
+    }
+};