number of 1 bits solution

Author: wooseok123

number-of-1-bits/wooseok123.js

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+let hammingWeight = function (n) {
+  return DecToBinAndGetSetBits(n);
+};
+
+// TC : O(log n) | SC : O(1)
+
+let DecToBinAndGetSetBits = (n) => {
+  let targetNum = n;
+  let result = 0;
+  while (targetNum > 0) {
+    let remainder = targetNum % 2;
+    if (remainder === 1) result += 1;
+    targetNum = parseInt(targetNum / 2);
+  }
+  return result;
+};
+
+// TC : O(log n) | SC : O(log n)
+// 근데 사실 split 메서드 자체는 o(n)인데, toString과정을 통해 log(n)의 개수만큼 나와버린 것이면 o(log n)이라고 표기해도 되는걸까?
+
+// let DecToBinAndGetSetBits = (n) => {
+//     let target = n;
+//     let bin = n.toString(2);
+//     return bin.split("").filter((el) => el == 1).length
+// }
+
+// TC : O(log n) | SC : O(log n)
+
+// let DecToBinAndGetSetBits = (n) => {
+//     let target = n;
+//     let bin = n.toString(2);
+//     let matches = bin.match(/1/g);
+//     return matches.length
+// }