题目：
题解：
int hIndex(int* citations, int citationsSize) {
int left = 0, right = citationsSize - 1;
while (left <= right) {
int mid = left + (right - left) / 2;
if (citations[mid] >= citationsSize - mid) {
right = mid - 1;
} else {
left = mid + 1;
}
}
return citationsSize - left;
}
