4-11-liang.cpp

Debugged example from class (W week 4):

#include <iostream>
using namespace std;

const int NUMBER_OF_PRIMES = 50;
const int NUMBER_OF_PRIMES_PER_LINE = 10;

int main(){

  int count = 0; // Count the number of prime numbers
  int number = 2; // A number to be tested for primeness
  bool isPrime; // Is the current number prime?
  int divisor; // loop control var

  cout << "The first 50 prime numbers are \n";

  //generate 50 primes
  while (count < NUMBER_OF_PRIMES){
    // Test if number is prime
    divisor = 2;
    while (number % divisor != 0)
      divisor++;
    // prime, if divisor == number
    isPrime = (divisor == number);

    //if number is prime, then print
    if (isPrime){
      //found one more
      count++; 
      //print in table
      if (count % NUMBER_OF_PRIMES_PER_LINE == 0){
         // Print & go to new line
         cout << number << endl;
      }
      else
         cout << number << " ";
    }

    //generate next potential prime
    number++;
  }
}

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