/
MergeSortedArrays.java
50 lines (40 loc) · 1.57 KB
/
MergeSortedArrays.java
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class Solution {
public void merge(int[] nums1, int m, int[] nums2, int n) {
// [2, 3, 4, 0, 0], first = 2, end = 4
// [1, 2] second = 1
// [2, 3, 0, 0, 4], first = 1, end = 3
// [1, 2] second = 1
// [2, 0, 0, 3, 4] first = 0, end = 2
// [1, 2] second = 1
// [2, 0, 2, 3, 4], first = 0, end = 1
// [1, 2] second = 0
// [0, 2, 2, 3, 4], first = -1, end = 0
// [1, 2] second = 0
// [1, 2, 2, 3, 4], first = -1, end = 0
// [1, 2] second = -1
// [1, 2, 0, 0]
// [4, 5]
// Logic, start from the end, swap if the nums1 pointer has higher value and send it to end
// Assign and remove 0 in nums1 with nums2 value if nusm2 value is more
int first = m - 1, second = n - 1, end = (m + n) - 1;
while (second != -1) {
if (first == -1) {
// We populate the remaining values of nums2
nums1[end--] = nums2[second--];
} else if (second == -1) {
// When this happens, array is already sorted
} else {
if (nums2[second] > nums1[first]) {
nums1[end--] = nums2[second--];
} else {
// Swap
int t = nums1[first];
nums1[first] = nums1[end];
nums1[end] = t;
first--;
end--;
}
}
}
}
}