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| 1 | +import java.io.BufferedReader; |
| 2 | +import java.io.IOException; |
| 3 | +import java.io.InputStreamReader; |
| 4 | +import java.util.ArrayList; |
| 5 | +import java.util.Collections; |
| 6 | +import java.util.List; |
| 7 | +import java.util.StringTokenizer; |
| 8 | + |
| 9 | +/** |
| 10 | + * 완전 틀림, 해결책 제시 X |
| 11 | + */ |
| 12 | +public class JM_1450 { |
| 13 | + static int N; |
| 14 | + static int C; |
| 15 | + static int[] W; |
| 16 | + |
| 17 | + private static int upperBound(int target, List<Integer> A) { |
| 18 | + int lo = 0; |
| 19 | + int hi = A.size() - 1; |
| 20 | + int ans = A.size(); |
| 21 | + while (lo <= hi) { |
| 22 | + int mid = (lo + hi) / 2; |
| 23 | + if(target < A.get(mid)) { |
| 24 | + ans = mid; |
| 25 | + hi = mid - 1; |
| 26 | + } |
| 27 | + else lo = mid + 1; |
| 28 | + } |
| 29 | + return ans; |
| 30 | + } |
| 31 | + |
| 32 | + private static void combi(int start, int end, int sum, List<Integer> combiSums) { |
| 33 | + if(sum > C) return; |
| 34 | + if(start == end) { |
| 35 | + combiSums.add(sum); |
| 36 | + return; |
| 37 | + } |
| 38 | + combi(start + 1, end, sum, combiSums); |
| 39 | + combi(start + 1, end, sum + W[start], combiSums); |
| 40 | + } |
| 41 | + |
| 42 | + private static int solve() { |
| 43 | + List<Integer> left = new ArrayList<>(); |
| 44 | + List<Integer> right = new ArrayList<>(); |
| 45 | + |
| 46 | + combi(0, N / 2, 0, left); |
| 47 | + combi(N / 2, N, 0, right); |
| 48 | + |
| 49 | + Collections.sort(right); |
| 50 | + |
| 51 | + int count = 0; |
| 52 | + for(int leftSum : left) { |
| 53 | + count += upperBound(C - leftSum, right); |
| 54 | + } |
| 55 | + return count; |
| 56 | + } |
| 57 | + |
| 58 | + public static void main(String[] args) throws IOException { |
| 59 | + BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); |
| 60 | + StringTokenizer st = new StringTokenizer(br.readLine()); |
| 61 | + N = Integer.parseInt(st.nextToken()); |
| 62 | + C = Integer.parseInt(st.nextToken()); |
| 63 | + W = new int[N]; |
| 64 | + |
| 65 | + st = new StringTokenizer(br.readLine()); |
| 66 | + for (int i = 0; i < N; i++) { |
| 67 | + W[i] = Integer.parseInt(st.nextToken()); |
| 68 | + } |
| 69 | + |
| 70 | + System.out.println(solve()); |
| 71 | + } |
| 72 | +} |
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