sample1.cc
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00029 
00030 // A sample program demonstrating using Google C++ testing framework.
00031 //
00032 // Author: wan@google.com (Zhanyong Wan)
00033 
00034 #include "sample1.h"
00035 
00036 // Returns n! (the factorial of n).  For negative n, n! is defined to be 1.
00037 int Factorial(int n) {
00038   int result = 1;
00039   for (int i = 1; i <= n; i++) {
00040     result *= i;
00041   }
00042 
00043   return result;
00044 }
00045 
00046 // Returns true iff n is a prime number.
00047 bool IsPrime(int n) {
00048   // Trivial case 1: small numbers
00049   if (n <= 1) return false;
00050 
00051   // Trivial case 2: even numbers
00052   if (n % 2 == 0) return n == 2;
00053 
00054   // Now, we have that n is odd and n >= 3.
00055 
00056   // Try to divide n by every odd number i, starting from 3
00057   for (int i = 3; ; i += 2) {
00058     // We only have to try i up to the squre root of n
00059     if (i > n/i) break;
00060 
00061     // Now, we have i <= n/i < n.
00062     // If n is divisible by i, n is not prime.
00063     if (n % i == 0) return false;
00064   }
00065 
00066   // n has no integer factor in the range (1, n), and thus is prime.
00067   return true;
00068 }


rc_visard_driver
Author(s): Heiko Hirschmueller , Christian Emmerich , Felix Ruess
autogenerated on Thu Jun 6 2019 20:43:06