Easy Sliding window Java O(n) beats 100%
```\npublic int numberOfSubstrings(String s) {\n        int i=0,j=0,result = 0,n = s.length();\n        int[] tracker = new int[3];\n        while(j 0 && tracke
```\npublic int numberOfSubstrings(String s) {\n        int i=0,j=0,result = 0,n = s.length();\n        int[] tracker = new int[3];\n        while(j<n){\n            char c = s.charAt(j);\n            tracker[c -\'a\']++;\n            while(tracker[0] > 0 && tracker[1]>0 && tracker[2]>0){\n                result = result + n-j;\n                tracker[s.charAt(i++) -\'a\']--;\n            }\n            j++;\n        }\n        return result;\n    }
['Sliding Window', 'Java']