[C++知识库]PAT甲级 1048（C++）

#include<iostream>
#include<algorithm>
#include<vector>
using namespace std;
int N, M;
vector<int>coins;
int  search(int first,int low, int high) {
	int mid = (low + high) / 2;
	if (low > high) return -1;
	if (coins[mid] == M - first) {
		return mid;
	}
	else if (coins[mid] > M - first) {
		high = mid - 1;
		return search(first, low, high);
	}
	else {
		low = mid + 1;
		return search(first, low, high);
	}
}
int main() {
	cin >> N >> M;
	for (int i = 1; i <= N; i++) {
		int temp; cin >> temp;
		coins.push_back(temp);
	}
	sort(coins.begin(), coins.end());
	for (int i = 1; i < N; i++) {
		int second = search(coins[i - 1], i, N - 1);
		if (second != -1) {
			cout << coins[i-1] << " " << coins[second];
			return 0;
		}
	}
	cout << "No Solution";
	return 0;
}