c_cpp 二进制搜索模板

Posted 2021-05-14

int solve(int left, int right) {
	int mid;
	while (left < right) {
		mid = left + (right - left) / 2;;
		if (/*条件成立*/) {
			/*
			 * lower_bound(): a[mid] >= val
			 * upper_bound(): a[mid] > val
			 */
			right = mid;
		}
		else {
			left = mid + 1;
		}
	}
	return left;
}