@@ -219,6 +219,54 @@ else if (target <= nums[right]) {
219219 }
220220 }
221221
222+ /**
223+ * longest substring without repeating characters
224+ * */
225+ 226+ public static int lengthOfLongestSubstring (String s ) {
227+ // a b c a b c b b
228+ // 0 1 2 3 4 5 6 7
229+ if (s .length () <= 1 )
230+ return s .length ();
231+ Map <Character , Integer > seenCharacters = new HashMap <>();
232+ int left = 0 , longest = 0 ;
233+ for (int right = 0 ; right < s .length (); right ++) {
234+ char currentChar = s .charAt (right );
235+ if (null != seenCharacters .get (currentChar ) && seenCharacters .get (currentChar ) >= left ) {
236+ left = seenCharacters .get (currentChar ) + 1 ;
237+ }
238+ longest = Math .max (longest , right -left +1 );
239+ seenCharacters .put (currentChar , right );
240+ }
241+ 242+ return longest ;
243+ 244+ }
245+ 246+ /**
247+ * Container with largest amount of water
248+ * concept - 2 shifting pointers
249+ */
250+ public static int maxArea (int [] height ) {
251+ 252+ if (height .length <= 1 ) return 0 ;
253+ 254+ int left = 0 ;
255+ int right = height .length - 1 ;
256+ int maxArea = 0 ;
257+ 258+ while (left <= right ) {
259+ int leftNum = height [left ];
260+ int rightNum = height [right ];
261+ 262+ maxArea = Math .max (maxArea , Math .min (leftNum , rightNum ) * (right -left ));
263+ if (leftNum < rightNum ) left ++;
264+ else right --;
265+ }
266+ 267+ return maxArea ;
268+ }
269+ 222270 public static void main (String [] args ) {
223271 int index = search (new int []{2 ,2 ,2 ,3 ,4 ,2 }, 3 , 0 , 5 );
224272 System .out .println ("index of 3 is " + index );
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