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  1. import java.util.InputMismatchException;
  2. import java.io.IOException;
  3. import java.io.InputStream;
  4. import java.io.PrintWriter;
  5. import java.util.Arrays;
  6. class LCPC12F{
  7.     public static void main(String args[])throws IOException{
  8.         InputReader sc = new InputReader(System.in);
  9.         PrintWriter pw = new PrintWriter(System.out);
  10.  
  11.         int t = sc.nextInt();
  12.         for(int q=1; q<=t; q++){
  13.             int x = sc.nextInt(), n = sc.nextInt();
  14.             int arr[] = new int[n], ans = 0;
  15.             for(int i=0; i<n; i++)
  16.                 arr[i] = sc.nextInt();
  17.             Arrays.sort(arr);
  18.  
  19.             int j = 0, k = n-1;
  20.             while(j<k){
  21.                 if(arr[j]+arr[k] == x){
  22.                     ans++;
  23.                     j++;
  24.                 }
  25.                 else if(arr[j] + arr[k]<x)
  26.                     j++;
  27.                 else
  28.                     k--;
  29.             }
  30.             pw.println(+q+". "+ans);
  31.         }
  32.         pw.flush();
  33.         pw.close();
  34.     }
  35.     static class InputReader {
  36.         private final InputStream stream;
  37.         private final byte[] buf = new byte[8192];
  38.         private int curChar, snumChars;
  39.         private SpaceCharFilter filter;
  40.  
  41.         public InputReader(InputStream stream) {
  42.             this.stream = stream;
  43.         }
  44.  
  45.         public int snext() {
  46.             if (snumChars == -1)
  47.                 throw new InputMismatchException();
  48.             if (curChar >= snumChars) {
  49.                 curChar = 0;
  50.                 try {
  51.                     snumChars = stream.read(buf);
  52.                 } catch (IOException e) {
  53.                     throw new InputMismatchException();
  54.                 }
  55.                 if (snumChars <= 0)
  56.                     return -1;
  57.             }
  58.             return buf[curChar++];
  59.         }
  60.  
  61.         public int nextInt() {
  62.             int c = snext();
  63.             while (isSpaceChar(c)) {
  64.                 c = snext();
  65.             }
  66.             int sgn = 1;
  67.             if (c == '-') {
  68.                 sgn = -1;
  69.                 c = snext();
  70.             }
  71.             int res = 0;
  72.             do {
  73.                 if (c < '0' || c > '9')
  74.                     throw new InputMismatchException();
  75.                 res *= 10;
  76.                 res += c - '0';
  77.                 c = snext();
  78.             } while (!isSpaceChar(c));
  79.             return res * sgn;
  80.         }
  81.  
  82.         public long nextLong() {
  83.             int c = snext();
  84.             while (isSpaceChar(c)) {
  85.                 c = snext();
  86.             }
  87.             int sgn = 1;
  88.             if (c == '-') {
  89.                 sgn = -1;
  90.                 c = snext();
  91.             }
  92.             long res = 0;
  93.             do {
  94.                 if (c < '0' || c > '9')
  95.                     throw new InputMismatchException();
  96.                 res *= 10;
  97.                 res += c - '0';
  98.                 c = snext();
  99.             } while (!isSpaceChar(c));
  100.             return res * sgn;
  101.         }
  102.  
  103.         public int[] nextIntArray(int n) {
  104.             int a[] = new int[n];
  105.             for (int i = 0; i < n; i++) {
  106.                 a[i] = nextInt();
  107.             }
  108.             return a;
  109.         }
  110.  
  111.         public String readString() {
  112.             int c = snext();
  113.             while (isSpaceChar(c)) {
  114.                 c = snext();
  115.             }
  116.             StringBuilder res = new StringBuilder();
  117.             do {
  118.                 res.appendCodePoint(c);
  119.                 c = snext();
  120.             } while (!isSpaceChar(c));
  121.             return res.toString();
  122.         }
  123.  
  124.         public String nextLine() {
  125.             int c = snext();
  126.             while (isSpaceChar(c))
  127.                 c = snext();
  128.             StringBuilder res = new StringBuilder();
  129.             do {
  130.                 res.appendCodePoint(c);
  131.                 c = snext();
  132.             } while (!isEndOfLine(c));
  133.             return res.toString();
  134.         }
  135.  
  136.         public boolean isSpaceChar(int c) {
  137.             if (filter != null)
  138.                 return filter.isSpaceChar(c);
  139.             return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
  140.         }
  141.  
  142.         private boolean isEndOfLine(int c) {
  143.             return c == '\n' || c == '\r' || c == -1;
  144.         }
  145.  
  146.         public interface SpaceCharFilter {
  147.             public boolean isSpaceChar(int ch);
  148.         }
  149.     }
  150. }
Success #stdin #stdout 0.06s 27920KB
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https://ideone.com/Re0dY9
language:
Java (HotSpot 12)
created:
5 years ago
visibility:
public

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