Array Practice Programs

int[] arr = {10, 20, 30, 40, 50}; int target = 30; int result = -1; for (int i = 0; i < arr.length; i++) { if (arr[i] == target) { result = i; break; } } System.out.println(result != -1 ? "Mila index: " + result : "Nahi mila");

void rotateLeft(int[] arr, int k) { int n = arr.length; k = k % n; reverse(arr, 0, k-1); reverse(arr, k, n-1); reverse(arr, 0, n-1); } void reverse(int[] arr, int l, int r) { while (l < r) { int t = arr[l]; arr[l] = arr[r]; arr[r] = t; l++; r--; } }

int removeDuplicates(int[] arr) { if (arr.length == 0) return 0; int k = 1; for (int i = 1; i < arr.length; i++) if (arr[i] != arr[i-1]) arr[k++] = arr[i]; return k; // unique elements count }

int maxSubarraySum(int[] arr) { int maxSum = arr[0], currentSum = arr[0]; for (int i = 1; i < arr.length; i++) { currentSum = Math.max(arr[i], currentSum + arr[i]); maxSum = Math.max(maxSum, currentSum); } return maxSum; }

int[] merge(int[] a, int[] b) { int[] result = new int[a.length + b.length]; int i = 0, j = 0, k = 0; while (i < a.length && j < b.length) result[k++] = (a[i] < b[j]) ? a[i++] : b[j++]; while (i < a.length) result[k++] = a[i++]; while (j < b.length) result[k++] = b[j++]; return result; }