a binary format problem

Author: HaFred

python/2571_Minimum_Operations_Reduce_Int_ 0.py

@@ -0,0 +1,33 @@
+# not dp, but using binary as the question is all about binary operations.
+class Solution:
+    def minOperations(self, n):
+        if n == 0:
+            return 0
+        if n == 1:
+            return 0
+        if n < 0:
+            return 0
+
+        # do comparison with either makes up with 1 or not
+        ret = 0
+        # pos int n means it is single precision
+        for i in range(32):
+            if self.count_1(n + (1 << i)) + 1 <= self.count_1(n):  # in fact, it considers the case of subtraction, coz if it is 0b'10000000001, apparently it won't get into the loop, and the result will just ret + self.count_1(n), which is done by doing substation
+                n += 1 << i
+                ret += 1
+        return ret + self.count_1(n)
+
+    def count_1(self, n):
+        binary_n = bin(n)
+        return binary_n.count('1')
+
+
+# indata = [3, 2, 0, -4]
+# pos = 1
+# indata = 39
+# output = 3
+indata = 54
+output = 3
+sol = Solution()
+out = sol.minOperations(indata)
+print(out)