algo-aha

分成一些k长连续整数

• https://leetcode.com/problems/hand-of-straights/
• https://leetcode.com/problems/divide-array-in-sets-of-k-consecutive-numbers/

bool isPossibleDivide(vector<int>& nums, int k) {
    map<int, int> cnt; // num=>count
    for (int num : nums) {
        cnt[num]++;
    }
    
    for (auto &e : cnt) {
        int count = e.second;
        if (count > 0) { // [num..num+k)都减count
            int num = e.first;
            for (int i = 0; i < k; i++) {
                cnt[num+i] -= count;
                if (cnt[num+i] < 0) return false;
            }
        }
    }
    return true;
}