@@ -12,97 +12,49 @@ public class SmallestWindowContaingAllCharacters {
1212
1313 public String minWindow (String s , String t ) {
1414 Map <Character , Integer > countMap = new HashMap <>();
15- for (char s1 : t .toCharArray ()) {
16- countMap .compute (s1 , (key , val ) -> {
17- if (val == null ) {
18- return 1 ;
19- }
20- return val + 1 ;
21- });
22- }
23- 24- Map <Character , Integer > foundMap = new HashMap <>();
25- for (char s1 : t .toCharArray ()) {
26- foundMap .put (s1 , 0 );
27- }
28- 29- int startWindow ;
30- int charsFound = 0 ;
31- for (startWindow = 0 ; startWindow < s .length (); startWindow ++) {
32- if (countMap .containsKey (s .charAt (startWindow ))) {
33- break ;
15+ for (char ch : t .toCharArray ()) {
16+ Integer val = countMap .get (ch );
17+ if (val == null ) {
18+ val = 0 ;
3419 }
20+ countMap .put (ch , val + 1 );
3521 }
36- int minWindowStart = Integer .MIN_VALUE ;
37- int minWindowEnd = -1 ;
38- int totalCharacters = t .length ();
39- for (int i = startWindow ; i < s .length (); i ++) {
40- char ch = s .charAt (i );
41- Integer count = countMap .get (ch );
42- if (count != null ) {
43- Integer actualCount = foundMap .get (ch );
44- foundMap .put (ch , actualCount + 1 );
45- if (actualCount < count ) {
46- charsFound ++;
47- if (charsFound == totalCharacters ) {
48- if (i - startWindow < minWindowEnd - minWindowStart ) {
49- minWindowStart = startWindow ;
50- minWindowEnd = i ;
51- }
52- ShrinkResult sr = shrinkWindow (countMap , foundMap , startWindow , s , i );
53- if (sr .fullStartWindow != -1 ) {
54- if (i - sr .fullStartWindow < minWindowEnd - minWindowStart ) {
55- minWindowStart = sr .fullStartWindow ;
56- minWindowEnd = i ;
57- }
58- }
59- startWindow = sr .startWindow ;
60- charsFound --;
61- }
62- }
22+ int start = 0 ;
23+ int currLen = t .length ();
24+ int minWindow = Integer .MAX_VALUE ;
25+ int minStart = 0 ;
26+ int i = 0 ;
27+ while (i < s .length ()) {
28+ Integer val = countMap .get (s .charAt (i ));
29+ if (val == null ) {
30+ i ++;
31+ continue ;
6332 }
64- }
65- if (minWindowEnd == -1 ) {
66- return "" ;
67- } else {
68- return s .substring (minWindowStart , minWindowEnd + 1 );
69- }
70- }
71- 72- class ShrinkResult {
73- int startWindow ;
74- int fullStartWindow ;
75- }
76- 77- private ShrinkResult shrinkWindow (Map <Character , Integer > countMap , Map <Character , Integer > foundMap ,
78- int startWindow , String s , int end ) {
79- boolean firstViolation = false ;
80- int diff = -1 ;
81- int i ;
82- for (i = startWindow ; i <= end ; i ++) {
83- if (!firstViolation ) {
84- diff = i ;
33+ if (val > 0 ) {
34+ currLen --;
8535 }
86- char ch = s .charAt (i );
87- Integer count = countMap .get (ch );
88- if (count != null ) {
89- int actualCount = foundMap .get (ch );
90- if (firstViolation ) {
91- if (actualCount <= count ) {
36+ val --;
37+ countMap .put (s .charAt (i ), val );
38+ while (currLen == 0 ) {
39+ if (minWindow > i - start + 1 ) {
40+ minWindow = i - start + 1 ;
41+ minStart = start ;
42+ }
43+ Integer val1 = countMap .get (s .charAt (start ));
44+ if (val1 != null ) {
45+ if (val1 == 0 ) {
9246 break ;
93- }
94- } else {
95- if (actualCount == count ) {
96- firstViolation = true ;
47+ } else {
48+ val1 ++;
49+ countMap .put (s .charAt (start ), val1 );
9750 }
9851 }
99- foundMap . compute ( ch , ( key , val ) -> val - 1 ) ;
52+ start ++ ;
10053 }
54+ i ++;
10155 }
102- ShrinkResult sr = new ShrinkResult ();
103- sr .fullStartWindow = diff ;
104- sr .startWindow = i ;
105- return sr ;
56+ 57+ return minWindow != Integer .MAX_VALUE ? s .substring (minStart , minStart + minWindow ) : "" ;
10658 }
10759
10860 public static void main (String args []) {
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