private static void MergeSort(int[] array, int start, int end){
        if(start>=end)return;
        int mid = (start+end)/2;
        MergeSort(array, start, mid);
        MergeSort(array, mid+1, end);
        MergeOne(array, start, mid, end);
}
private static void MergeOne(int[] array, int start, int mid, int end) {
    int[] temp = new int[end-start+1];
    int k=0,i=start,j=mid+1;
    while(i<=mid && j<= end) {
        //如果前面的元素小于后面的不能构成逆序对
        if(array[i] <= array[j]) {
            temp[k++] = array[i++];
        } else {  //如果前面的元素大于后面的，那么在前面元素之后的元素都能和后面的元素构成逆序对
            temp[k++] = array[j++];
        }
    }
    while(i <= mid)
        temp[k++] = array[i++];
    while( j<= end)
        temp[k++] = array[j++];

    for(int l=0; l<k; l++) {
        array[start+l] = temp[l];
    }
}

public static void main(String[] args) {
    int[] array = new int[]{1, 100, 45, 98, 8, 30, 30, 66, 2, 100, 1};
    MergeSort(array, 0, array.length - 1);
    for (int i : array) {
        System.out.println(i);
    }
}

/*
* @nums：排序数组
* @target：要搜索的值
* @return：-1，没有target值;!=-1,target在nums中的索引
*/
public int binarySearch(int[] nums, int target) {
    int left = 0; 
    int right = nums.length - 1; 

    while(left <= right) { 
        int mid = left + (right- left) / 2;
        if(nums[mid] == target)
            return mid; 
        else if (nums[mid] < target)
            left = mid + 1; 
        else if (nums[mid] > target)
            right = mid - 1; 
        }
    return -1;
}

String[] strs = new String[]{"Srammy", "要努力学", "JAVA!"};
String a = "";
for(String s : strs) {
    a = a + s;
}
System.out.println(a); // 输出---> Srammy要努力学JAVA!