Create 1864-minimum-number-of-swaps-to-make-the-binary-string-alternating.js

Author: everthis

1864-minimum-number-of-swaps-to-make-the-binary-string-alternating.js

@@ -0,0 +1,53 @@
+/**
+ * @param {string} s
+ * @return {number}
+ */
+const minSwaps = function(s) {
+  const valid = chk(s)
+  if(valid === -1) return -1
+  const [zeroNum, oneNum] = valid
+  let res = Infinity
+  if(zeroNum === oneNum) {
+    // zero start
+    let tmpZero = 0
+    let cur = '0'
+    for(let i = 0; i < s.length; i++) {
+      if(i % 2 === 0 && s[i] !== '0') tmpZero++
+    }
+    
+    res = Math.min(tmpZero, res)
+    // one start
+    let tmpOne = 0
+    cur = '1'
+    for(let i = 0; i < s.length; i++) {
+      if(i % 2 === 0 && s[i] !== '1') tmpOne++
+    }
+    res = Math.min(tmpOne, res)
+  } else if(zeroNum > oneNum) {
+    let tmpZero = 0
+    let cur = '0'
+    for(let i = 0; i < s.length; i++) {
+      if(i % 2 === 0 && s[i] !== '0') tmpZero++
+    }
+    
+    res = Math.min(tmpZero, res)     
+  } else {
+    let tmpOne = 0
+    cur = '1'
+    for(let i = 0; i < s.length; i++) {
+      if(i % 2 === 0 && s[i] !== '1') tmpOne++
+    }
+    res = Math.min(tmpOne, res)
+  }
+  return res
+};
+
+function chk(str) {
+  let oneNum = 0, zeroNum = 0
+  for(let ch of str) {
+    if(ch === '0') zeroNum++
+    else oneNum++
+  } 
+  return Math.abs(zeroNum - oneNum) <= 1 ? [zeroNum, oneNum] : -1
+}
+