Bubble Sort

BubbleSort.cpp

void BubbleSort(int* numbers, int length) {
    if(numbers == NULL || length <= 1) return;
    for(int i = length; i > 0; i--) {
        for(int j = 0; j + 1 < length; j++) {
            if(numbers[j] > numbers[j+1]) {
                int tmp = numbers[j];
                numbers[j] = numbers[j+1];
                numbers[j+1] = tmp;
            }
        }
    }
}

InsertSort.cpp

void InsertSort(int* numbers, int length) {
    if(numbers == NULL || length <= 1) return;
    for(int i = 1; i < length; ++i) {
        int val = numbers[i];
        int j;
        for(j = i-1; j >= 0; --j) {
            if(val < numbers[j])
                numbers[j+1] = numbers[j];
            else
                break;
        }
        numbers[j+1] = val;
    }
}

MergeSort.cpp

void MergeSort(int* numbers, int length) {
    if(numbers == NULL || length <= 1) return;
    int* tempArr = new int[length];
    int mid = (length - 1) / 2;
    MergeSortEx(numbers, 0, mid, tempArr);
    MergeSortEx(numbers, mid+1, length-1, tempArr);
    Merge(number, 0, length-1, mid, tempArr);
    delete [] tempArr;
}

void MergeSortEx(int* numbers, int left, int right, int* tempArr) {
    if(left == right) return;
    if(left + 1 == right) {
        if(numbers[left] > numbers[right]) {
            int tmp = numbers[left];
            numbers[left] = numbers[right];
            numbers[right] = tmp;
        }
        return;
    }
    int mid = (left + right) / 2;
    MergeSortEx(numbers, left, mid, tempArr);
    MergeSortEx(numbers, mid+1, right, tempArr);
    Merge(numbers, left, right, mid, tempArr);
}

void Merge(int* numbers, int left, int right, int mid, int* tempArr) {
    int i = left, j = mid + 1, k = 0;
    while(i <= mid && j <= right) {
        if(numbers[i] <= numbers[j]) {
            tempArr[k++] = numbers[i++];
        } else {
            tempArr[k++] = numbers[j++];
        }
    }
    while(i <= mid) tempArr[k++] = numbers[i++];
    while(j <= right) tempArr[k++] = numbers[j++];
    memcpy(numbers + left, tempArr, k * sizeof(int));
    return;
}