From 290ced42d1314ef3cc299dc0f7c5473a267599e8 Mon Sep 17 00:00:00 2001
From: Christoph Fuerst <ch.fuerst@gmx.at>
Date: Sun, 26 Mar 2017 20:22:33 +0200
Subject: [PATCH] Added menu dialog

---
 src/primefactors.cpp | 103 ++++++++++++++++++++++++++++++++++-----------------
 1 file changed, 68 insertions(+), 35 deletions(-)

diff --git a/src/primefactors.cpp b/src/primefactors.cpp
index 7de4e33..45a1498 100644
--- a/src/primefactors.cpp
+++ b/src/primefactors.cpp
@@ -100,45 +100,78 @@ void factor_int2(mpz_class N)
 	cout << "Found prime-factors: " << (a-b)/2 << " and " << ((a+b-2)/2) << endl;
 }
 
-int main()
+int main(int argc, char** argv)
 {
-   mpz_class N;
-   mpz_class *trialdivisors, *factors;
-   unsigned long max;
-   unsigned long nooffactors;
-
-   cout << "Enter Integer to be factored.... ";
-   cin >> N;
-   cout << endl;
-
-   max = (unsigned long)(sqrt(N.get_ui()));
-
-   trialdivisors = new mpz_class[max];
-   factors = new mpz_class[max];
-
-   trialdivisors[0] = 2;
-   trialdivisors[1] = 3;
-   trialdivisors[2] = 5;
-   for(unsigned int i=3;i<max;i++)
+   if(argc == 1)
    {
-      if(i%2 == 1)
-      {
-    	  trialdivisors[i] = trialdivisors[i-1]+2;
-      }
-      else
-      {
-    	  trialdivisors[i] = trialdivisors[i-1]+4;
-      }
+	   char input = '0';
+
+	   do
+	   {
+		   cout << "What do you want to do..." << endl;
+		   cout << "Algorithm A: Trial division" << endl;
+		   cout << "Algorithm C: Fermat like factorization" << endl;
+           cin >> input;
+           cout << endl;
+	   }while((input != 'A') && (input != 'C') );
+
+	   switch(input)
+	   {
+	   	   case 'A':
+	   	   {
+	   		   cout << "Select Trial divison" << endl;
+	   		   mpz_class N;
+	   		   mpz_class *trialdivisors, *factors;
+	   		   unsigned long max;
+	   		   unsigned long nooffactors;
+
+	   		   cout << "Enter Integer to be factored.... ";
+	   		   cin >> N;
+	   		   cout << endl;
+
+	   		   max = (unsigned long)(sqrt(N.get_ui()));
+
+	   		   trialdivisors = new mpz_class[max];
+	   		   factors = new mpz_class[max];
+
+	   		   trialdivisors[0] = 2;
+	   		   trialdivisors[1] = 3;
+	   		   trialdivisors[2] = 5;
+	   		   for(unsigned int i=3;i<max;i++)
+	   		   {
+	   		      if(i%2 == 1)
+	   		      {
+	   		    	  trialdivisors[i] = trialdivisors[i-1]+2;
+	   		      }
+	   		      else
+	   		      {
+	   		    	  trialdivisors[i] = trialdivisors[i-1]+4;
+	   		      }
+	   		   }
+
+	   		   factor_int(N, trialdivisors, nooffactors, factors);
+
+	   		   for(unsigned long i=0;i<=nooffactors;i++)
+	   			   cout << factors[i] << " ";
+	   		   cout << endl;
+	   		   break;
+	   	   }
+	   	   case 'C':
+	   	   {
+	   		   cout << "Select Fermat like factorization" << endl;
+	   		   cout << "ATTENTION: Only works proper if there are exactly 2 (!) prime factors" << endl;
+	   		   mpz_class N;
+	   		   cout << "Enter Integer to be factored.... ";
+	   		   cin >> N;
+	   		   cout << endl;
+	   		   factor_int2(N);
+	   		   break;
+	   	   }
+	   	   default:
+	   		   break;
+	   }
    }
 
-   factor_int(N, trialdivisors, nooffactors, factors);
-
-   for(unsigned long i=0;i<=nooffactors;i++)
-	   cout << factors[i] << " ";
-   cout << endl;
-
-   factor_int2(N);
-
    return (0);
 }
 
-- 
2.1.4