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vikp

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clean_code

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ERROR: type should be string, got "https://leetcode.com/problems/subarray-sums-divisible-by-k/\r\n//Problem no : 974\r\n\r\n/*\r\nExplanation:\r\nExtension of subarray whose sum equal to k\r\nUse prefix sum Array and HashMap\r\nWhile creating prefix array we will only note remainder in prefix array\r\n note: If remiander is negative add+k so remainder become positive\r\n i.e if -1 is remainder of num=-1 and k=5 but -1 is equivivalnet to 4=(-1+5)=(num+k)\r\nHashMap will be (number,frequency)\r\nIf prefix sum at two index equal then we will add frequency to answer\r\nThere are two menthods for counting answer\r\n 1)Calculate answer at time of adding value in HashMap only\r\n we will add frequency directly to answer\r\n 2)first add all prefix values in HashMap\r\n then calculate answer by adding all permutation of equal number\r\n\ti.e if v is frequency for num then we will add (v*(v-1)/2)\r\n\tsuppose we have num 1 for frequency 4 i.e. (1,1,1,1)\r\n\tThen we will add (4*(4-1)/2) to answer.i.e 3+2+1=6\r\n*/\r\nclass Solution {\r\n public int subarraysDivByK(int[] A, int k) {\r\n HashMap<Integer,Integer> h=new HashMap<Integer,Integer>();\r\n int n=A.length;\r\n int pre[]=new int[n];\r\n pre[0]=A[0]%k;\r\n if(pre[0]<0)\r\n pre[0]=pre[0]+k;\r\n for(int i=1;i<n;i++)\r\n {\r\n pre[i]=(pre[i-1]+A[i])%k;\r\n if(pre[i]<0)\r\n pre[i]=pre[i]+k;\r\n }\r\n h.put(0,1);\r\n int ans=0;\r\n for(int i=0;i<n;i++)\r\n {\r\n if(h.containsKey(pre[i]))\r\n ans+=h.get(pre[i]);\r\n h.put(pre[i],h.getOrDefault(pre[i],0)+1);\r\n }\r\n return ans;\r\n }\r\n}\r\n\r\n//Here Using Array instaed HashMap so speed is Faster\r\n//As Every value in pre[] is less than k (we are taking mod in every)\r\n//So Array will be of size k only\r\nclass Solution {\r\n public int subarraysDivByK(int[] A, int k) {\r\n int n=A.length;\r\n int h[]=new int[k];\r\n int pre[]=new int[n];\r\n pre[0]=A[0]%k;\r\n if(pre[0]<0)\r\n pre[0]=pre[0]+k;\r\n for(int i=1;i<n;i++)\r\n {\r\n pre[i]=(pre[i-1]+A[i])%k;\r\n if(pre[i]<0)\r\n pre[i]=pre[i]+k;\r\n }\r\n h[0]=1;\r\n int ans=0;\r\n for(int i=0;i<n;i++)\r\n {\r\n ans+=h[pre[i]];\r\n h[pre[i]]++;\r\n }\r\n return ans;\r\n }\r\n}"