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package algs14;
import stdlib.*;
/* ***********************************************************************
 *  Compilation:  javac OneSum.java
 *  Execution:    java OneSum input.txt
 *  Dependencies: In.java Stopwatch.java
 *
 *  A program with N running time. Read in N integers
 *  and counts the number that are exactly 0.
 *
 *  % java OneSum 2Kints.txt
 *  0
 *************************************************************************/

public class XOneSum {

  // print indices i such that a[i] = 0
  public static void printAll(int[] a) {
    int N = a.length;
    for (int i = 0; i < N; i++) {
      if (a[i] == 0) {
        StdOut.println(a[i]);
      }
    }
  }


  // return number of indices i such that a[i] = 0
  public static int count(int[] a) {
    int N = a.length;
    int cnt = 0;
    for (int i = 0; i < N; i++) {
      if (a[i] == 0) {
        cnt++;
      }
    }
    return cnt;
  }

  public static void main(String[] args)  {
    args = new String[] { "data/2Kints.txt" };
    int[] a = new In(args[0]).readAllInts();
    Stopwatch timer = new Stopwatch();
    int cnt = count(a);
    StdOut.println("elapsed time = " + timer.elapsedTime());
    StdOut.println(cnt);
  }
}