added the project files

projects/randomNumberGeneratorExamples/PRNG.cc

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+#include <iostream>
+#include <iomanip>
+using namespace std;
+#include <unistd.h>					// getpid
+#include "PRNG.h"
+
+PRNG prng1, prng2, prng3;				// global, normally one generator for entire program
+extern PRNG prng1;					// declaration to use prng1 in another translation unit
+
+int main() {
+    uint32_t seed = getpid();				// start with a pseudo random-number
+    prng1.seed( seed );					// synchronize all generators with same seed
+    prng2.seed( seed );
+    prng3.seed( seed );
+
+    // check 3 forms of generation are identical for 3 generators
+    for ( int i = 0; i < 10; i += 1 ) {			// generate 10 random numbers between 0-1
+	cout << prng1() % 2 << prng2( 1 ) << prng3( 0, 1 ) << endl;
+    }
+    cout << endl;
+    for ( int i = 0; i < 10; i += 1 ) {			// generate 10 random numbers between 5-21
+	cout << setw( 2 ) << prng1() % 17 + 5 << "  ";	// 0-16 + 5 = 5-21
+	cout << setw( 2 ) << prng2( 16 ) + 5 << "  ";
+	cout << setw( 2 ) << prng3( 5, 21 ) << endl;
+    }
+}

projects/randomNumberGeneratorExamples/PRNG.h

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+// Pseudo Random Number Generator : generate repeatable sequence of values that
+//   appear random by scrambling the bits of a 32-bit integer value.
+//
+// Interface :
+//   PRNG(s) - set starting seed 
+//   seed() - read seed
+//   seed(s) - reset seed
+//   prng() - generate random value in range [0,UINT_MAX]
+//   prng(u) - generate random value in range [0,u]
+//   prng(l,u) - generate random value in range [l,u]
+//
+// Examples : generate random number between 5-21
+//   prng() % 17 + 5	values 0-16 + 5 = 5-21
+//   prng( 16 ) + 5
+//   prng( 5, 21 )
+
+#ifndef __PRNG_H__
+#define __PRNG_H__
+
+#include <cstdint>					// uint32_t
+#include <cassert>					// assert
+
+class PRNG {
+    uint32_t  seed_;	// same results on 32/64-bit architectures
+  public:
+    PRNG( uint32_t  s = 362436069 ) {			// default seed
+	seed_ = s;					// set seed
+	assert( ((void)"invalid seed", seed_ != 0) );
+    }
+    uint32_t seed() {					// read seed
+	return seed_;
+    }
+    void seed( uint32_t  s ) {				// reset seed
+	seed_ = s;					// set seed
+	assert( ((void)"invalid seed", seed_ != 0) );
+    }
+    uint32_t operator()() {				// [0,UINT_MAX]
+	seed_ = 36969 * (seed_ & 65535) + (seed_ >> 16); // scramble bits
+	return seed_;
+    }
+    uint32_t operator()( uint32_t u ) {			// [0,u]
+	assert( ((void)"invalid random range", u < (uint32_t)-1) );
+	return operator()() % (u + 1);			// call operator()()
+    }
+    uint32_t operator()( uint32_t l, uint32_t u ) {	// [l,u]
+	assert( ((void)"invalid random range", l <= u) );
+	return operator()( u - l ) + l;			// call operator()( uint32_t )
+    }
+};
+
+#endif

projects/randomNumberGeneratorExamples/shuffle.cc

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+/*
+ * Example of using the <algorithm> std::shuffle and seeding a random number generator with either
+ * the command-line argument provided seed integer, or the current system time if there is no
+ * argument provided. Based off of the example at: 
+ *
+ *    http://www.cplusplus.com/reference/algorithm/shuffle/
+ *
+ *  Last updated: 2020-10-06
+ *  Copyright 2020 UW. All rights reserved.
+ *
+ */
+ // 
+#include <iostream>
+#include <string>
+#include <stdexcept>
+#include <vector>
+#include <algorithm>
+#include <random>
+#include <chrono>
+
+void print( std::vector<int> const & v ) {
+	for ( int i : v ) std::cout << i << ' ';
+	std::cout << std::endl;
+}
+
+int main( int argc, char * argv[] ) {
+	std::vector<int> v = { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
+
+	// use a time-based seed for the default seed value
+	unsigned seed = std::chrono::system_clock::now().time_since_epoch().count();
+	
+	if ( argc > 1 ) {
+		try {
+			seed = std::stoi( std::string{ argv[1] } );
+		} catch( std::invalid_argument & e ) {
+			std::cerr << e.what() << std::endl;
+			return 1;
+		} catch( std::out_of_range & e ) {
+			std::cerr << e.what() << std::endl;
+			return -1;
+		} // catch
+	} // if
+
+	std::default_random_engine rng{seed};
+
+	for ( int i = 0; i < 1000; i++ ) {
+		//std::shuffle( v.begin(), v.end(), std::default_random_engine(seed) );
+		std::shuffle( v.begin(), v.end(), rng );
+		print(v);		
+	} // for
+
+	return 0;
+} // main

projects/randomNumberGeneratorExamples/srand.cc

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+#include <iostream>
+#include <string>
+#include <stdlib.h> // srand/rand
+#include <sys/types.h> // getpid
+#include <unistd.h>
+using namespace std;
+
+void createRandomRow(int*& row, int size) {
+    row = new int[size];
+    for (int i = 0; i < size; ++i) row[i] = rand()%100;
+} // createRandomRow
+
+
+int main(int argc, char* argv[]) {
+    int seed = getpid();
+    if ( argc == 2 ) seed = stoi(string{argv[1]});
+    srand(seed); // only seed the random number generator once!
+
+    int *row = nullptr;
+    int size = rand() % 5 + 5;
+    createRandomRow(row, size);
+    cout << "row: ";
+    for (int i = 0; i < size; ++i) cout << row[i] << ' ';
+    cout << endl;
+    delete [] row;
+} // main