二分查找第一个比K大的数

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1.

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int find(vector<int> a, int k) {
	int l = 0, r = a.size();
	int id;
	while (l <= r) {
	
		int mid = l + (r - l) / 2;
		if (a[mid] > k) { 
			id = mid;
			r = mid - 1;
		} else {
			l = mid + 1;
		}
	}
	return id;
}

2.

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int binary(vector<int> v, int x) {
    int i = 0, j = v.size() - 1;
    while (i < j) {
        int mid = i + (j - i) / 2;
        if (v[mid] >= x) {
            j = mid;
        } else {
            i = mid + 1;
        }
       
    }
    
    return i;
}