力扣632.最小区间

滑动窗口，在所有出现的值中间移动，并且要去除重复出现的数

/**
 * Note: The returned array must be malloced, assume caller calls free().
 */
#define MAX_NUMS 180000

int compare(const void* a, const void* b)
{
    return *(int*)a - *(int*)b;
}

// 获得最大值和最小值，并且得到所有出现的数
void getRange(int* left, int* right, int** nums, int numsSize, int* numsColSize, int all[MAX_NUMS], int* allSize)
{
    int i, j;
    *left = INT_MAX;
    *right = INT_MIN;
    int tmp[MAX_NUMS] = {0};
    int tmpSize = 0;
    for (i = 0; i < numsSize; i++) {
        *left = *left < nums[i][0] ? *left : nums[i][0];
        *right = *right > nums[i][numsColSize[i] - 1] ? *right : nums[i][numsColSize[i] - 1];
        for (j = 0; j < numsColSize[i]; j++) {
            tmp[tmpSize] = nums[i][j];
            tmpSize += 1;
        }
    }

    qsort(tmp, tmpSize, sizeof(int), compare);

    all[*allSize] = tmp[0];   // 去重
    *allSize += 1;
    for (i = 1; i < tmpSize; i++) {
        if (tmp[i] != tmp[i - 1]) {
            all[*allSize] = tmp[i];
            *allSize += 1;
        }
    }
}

bool contain(int left, int right, int** nums, int numsSize, int* numsColSize)
{
    int i, j;
    bool flag = false;

    for (i = 0; i < numsSize; i++) {
        flag = false;
        if (left > nums[i][numsColSize[i] - 1] || right < nums[i][0]) {
            return false;
        }

        for (j = 0; j < numsColSize[i]; j++) {
            if (nums[i][j] >= left && nums[i][j] <= right) {
                flag = true;
                break;
            }
         }
         if (!flag) {
            return false;
         }
    }
    return true;
}
// 滑动窗口在所有出现的值中间移动，并且要去除重复出现的数
int* smallestRange(int** nums, int numsSize, int* numsColSize, int* returnSize){
    *returnSize = 2;
    int* result = (int*)malloc(sizeof(int) * 2);
    if (result == NULL) {
        return NULL;
    }
    int all[MAX_NUMS] = {0}; // 所有出现的数，不能重复
    int allSize = 0;
    int i, j;
    int left, right;
    getRange(&left, &right, nums, numsSize, numsColSize, all, &allSize);
    result[0] = left;
    result[1] = right;

    // 在所有出现的数中间滑动
    for (i = 0, j = 0; j < allSize; j++) {
        while (i <= j && contain(all[i], all[j], nums, numsSize, numsColSize)) {
            if ((all[j] - all[i]) < (result[1] - result[0]) || ((all[j] - all[i]) == (result[1] - result[0]) && (all[j] < result[1]))) {
                result[0] = all[i];
                result[1] = all[j];
            }
            i++;
        }
    }

    return result;
}