Update 8-string-to-integer-(atoi).js

Author: everthis

8-string-to-integer-(atoi).js

@@ -5,3 +5,33 @@
 const myAtoi = function(str) {
   return Math.max(Math.min(parseInt(str) || 0, 2147483647), -2147483648);
 };
+
+// anotther
+
+/**
+ * @param {string} s
+ * @return {number}
+ */
+const myAtoi = function(s) {
+    let n = s.length, i = 0, j = 0, sign = 1;
+    if(n === 0) {
+        return 0;
+    } 
+    while(i < n && s[i] === ' ') {
+        i++;
+    }
+    if(i < n && (s[i] === '-' || s[i] === '+')) {
+        sign = (s[i] === '-') ? -1 : 1;
+        i++;
+    }
+    j = i
+    while(i < n) {
+        if(Number.isInteger(parseInt(s[i]))) i++;
+        else break;
+    }
+    let result = parseInt(s.slice(j, i))
+    if(isNaN(result)) return 0
+    if(sign * result < -(2**31)) return -(2**31);
+    else if(sign * result > (2**31-1)) return 2**31-1;
+    else return sign * result;  
+};