Super Easy Java Solution or or 100% faster or or Easy to understand
Looking for Contribution in Hacktoberfest\n## You are welcomed to contribute in my Repos:-\n# GITHUB LINK --> Yaduttam95\n# All PRs are getting accepted...\n\n#
# Looking for Contribution in Hacktoberfest\n## You are welcomed to contribute in my Repos:-\n# GITHUB LINK --> [Yaduttam95](https://github.com/Yaduttam95)\n# All PRs are getting accepted...\n\n# Please upvote if Helpful\n```\nclass Solution {\n    public String minWindow(String s, String t) {\n        \n        \n        if(s=="" || t=="")\n            return "";\n        if(s==null || t==null)\n            return "";\n        \n        int n = s.length();\n        int m = t.length();\n        \n        \n        int freq[] = new int[128];\n        int characters = 0;\n        \n        for(int i=0;i<m;i++){\n            freq[t.charAt(i)]++;\n            characters++;\n        }\n        \n        int start =0, end = 0;\n        int min_length = Integer.MAX_VALUE;\n        int start_index = 0;\n        \n        while(end < n){\n            \n            if(freq[s.charAt(end)]>0)\n                characters--;\n            freq[s.charAt(end)]--;\n            end++;\n            \n            while(characters==0){\n                \n                if(min_length>end-start){\n                    min_length = end-start;\n                    start_index = start;\n                }\n                freq[s.charAt(start)]++;\n                if(freq[s.charAt(start)]>0){\n                    characters++;\n                }\n                start++;\n                \n            }\n            \n        }\n        \n        return min_length == Integer.MAX_VALUE? "" : s.substring(start_index,start_index+min_length);\n        \n    }\n}\n```\n![image](https://assets.leetcode.com/users/images/80bbe098-1d13-4e79-aba4-ff5f3522de19_1666336493.7066479.png)\n
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