K-Concatenation Maximum Sum LeetCode solution in Java

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class Solution {
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  int mod = 1000000007;
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  public int kadane(int[] a) {
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    int curr = 0;
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    int max = Integer.MIN_VALUE;
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    for (int i : a) {
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      curr += i;
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      if (curr < 0) curr = 0;
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      max = Math.max(max, curr);
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    }
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    return max % mod;
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  }
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  public int kConcatenationMaxSum(int[] arr, int k) {
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    int n = arr.length;
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    if (k == 1) return kadane(arr);
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    int[] temp = new int[2 * n];
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    for (int i = 0; i < n; i++) {
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      temp[i] = arr[i];
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      temp[n + i] = arr[i];
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    }
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    if (k == 2) return kadane(temp) % mod;
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    long sum = 0;
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    for (int i : arr) sum += i;
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    if (sum >= 0) return (int) ((kadane(temp) % mod) + ((sum % mod) * (k - 2) % mod) % mod);
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    else return (kadane(temp) % mod);
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  }
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}