switch Statement Example

	int alpha = 0; int beta = 0; int gamma = 0;  int n;
	cout << "Please enter a value of n for processing " << endl;
	cin >> n;
	cout << " The value you entered for n is " << n << endl;
	switch(n)
	{
	case 3:  alpha++;
	break;
	case 7:  beta++;
	break;
	case 10: gamma++;
	break;
	}
	cout << "alpha is " << alpha << endl << "beta is " << beta
	<< endl  << "gamma is " << gamma << endl;
	}

Loop Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int sum;
	int count;
	sum = 0;
	count = 1;
	while (count <= 1000)
	{
	sum = sum + count;
	count++;
	}
	cout << " The final sum is " << sum << endl;
	}

Equivalent for Statement

	#include <iostream>
	using namespace std;
	int main()
	{
	int sum;
	int count;
	sum = 0;
	for (count = 1; count <= 1000; count++)
	sum = sum + count;
	cout << " The final sum is " << sum << endl;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 4
	{
	for (j = 0; j < i; j++)
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 4
	{
	for (j = 0; j < i; j++) j = 0
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 4
	{
	for (j = 0; j < i; j++) j = 0
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 4
	{
	for (j = 0; j < i; j++) j = 1
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 4
	{
	for (j = 0; j < i; j++) j = 1
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 4
	{
	for (j = 0; j < i; j++) j = 2
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 4
	{
	for (j = 0; j < i; j++) j = 2
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 4
	{
	for (j = 0; j < i; j++) j = 3
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 4
	{
	for (j = 0; j < i; j++) j = 3
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 4
	{
	for (j = 0; j < i; j++) j = 4
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 4
	{
	for (j = 0; j < i; j++) j = 4
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 3
	{
	for (j = 0; j < i; j++) j = 4
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 3
	{
	for (j = 0; j < i; j++) j = 0
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 3
	{
	for (j = 0; j < i; j++) j = 0
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 3
	{
	for (j = 0; j < i; j++) j = 1
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 3
	{
	for (j = 0; j < i; j++) j = 1
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 3
	{
	for (j = 0; j < i; j++) j = 2
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 3
	{
	for (j = 0; j < i; j++) j = 2
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 3
	{
	for (j = 0; j < i; j++) j = 3
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 3
	{
	for (j = 0; j < i; j++) j = 3
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 2
	{
	for (j = 0; j < i; j++) j = 3
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 2
	{
	for (j = 0; j < i; j++) j = 0
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 2
	{
	for (j = 0; j < i; j++) j = 0
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 2
	{
	for (j = 0; j < i; j++) j = 1
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 2
	{
	for (j = 0; j < i; j++) j = 1
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 2
	{
	for (j = 0; j < i; j++) j = 2
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 2
	{
	for (j = 0; j < i; j++) j = 2
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 1
	{
	for (j = 0; j < i; j++) j = 2
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 1
	{
	for (j = 0; j < i; j++) j = 0
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 1
	{
	for (j = 0; j < i; j++) j = 0
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 1
	{
	for (j = 0; j < i; j++) j = 1
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 1
	{
	for (j = 0; j < i; j++) j = 1
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 0
	{
	for (j = 0; j < i; j++) j = 1
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

Nested for Example

	#include <iostream>
	using namespace std;
	int main()
	{
	int i;
	int j;
	for (i = 4; i >= 1; i--) i = 0
	{
	for (j = 0; j < i; j++) j = 1
	cout << j << "***";
	cout << i << endl;
	}
	return 0;
	}

do-while Statement Example

	int main()
	{
	int num; int count = 0; int sum = 0;
	do
	{
	cout << "Please enter a number for summing " << endl;
	cin >> num;
	if (num > 0)
	{
	sum = sum + num;
	count++;
	cout << "The number is " << num << endl;
	}
	} while ((num > 0) && (count < 10));
	cout << "The sum is " << sum << endl;
	}

Problem Solving Case Study

	Problem: Write an interactive program to enter 12 rainfall values for as many sites as the user wishes, averaging the 12 for each site.
	Input: 12 rainfall amounts (float) for each site, ‘y’ or ‘n’ answer to prompt for continuing (char)

Problem Solving Case Study

	Outputs: The average (float) for each site, displayed to two decimal places.
	Discussion: Several loops are required: one to process the data from all sites, one to sum the 12 values at each site, two more loops for data validation
	Assumption: The user processes data for at least one site.

Problem Solving Case Study

	//************************************************************
	// Rainfall program
	// This program inputs 12 monthly rainfall amounts from a
	// recording site and computes the average monthly rainfall.
	// This process is repeated for as many recording sites as
	// the user wishes.
	//************************************************************
	#include <iostream>
	#include <iomanip>    // For setprecision()
	using namespace std;
	void Get12Amounts( float& );
	void GetOneAmount( float& );
	void GetYesOrNo( char& );

Problem Solving Case Study

	int main()
	{
	float sum;           // Sum of 12 rainfall amounts
	char  response;      // User response ('y' or 'n')
	cout << fixed << showpoint          // Set up floating pt.
	<< setprecision(2);            //   output format
	do
	{
	Get12Amounts(sum);
	cout << endl << "Average rainfall is " << sum / 12.0
	<< " inches" << endl << endl;
	cout << "Do you have another recording site? (y or n) ";
	GetYesOrNo(response);
	} while (response == 'y');
	return 0;
	}

Problem Solving Case Study

	void Get12Amounts( /*out*/ float& sum ) // Sum of rainfall
	// Inputs 12 monthly rainfall amounts, verifying that
	// each is nonnegative, and returns their sum
	// Postcondition:
	//     12 nonnegative rainfall amounts have been read
	//  && sum == sum of the 12 input values
	{
	int   count;       // Loop control variable
	float amount;      // Rainfall amount for one month
	sum = 0;
	for (count = 1; count <= 12; count++)
	{
	cout << "Enter rainfall amount " << count << ": ";
	GetOneAmount(amount);
	sum = sum + amount;
	}
	}

Problem Solving Case Study

	void GetYesOrNo( /*out*/ char& response )  // User response char
	// Inputs a character from the user and, if necessary,
	// repeatedly prints an error message and inputs another
	// character if the character isn't 'y' or 'n'
	// Postcondition:
	//     response has been input (repeatedly, if necessary, along
	//     with output of an error message)
	//  && response == 'y' or 'n‘
	{
	do
	{
	cin >> response;
	if (response != 'y' && response != 'n')
	cout << "Please type y or n: ";
	} while (response != 'y' && response != 'n');
	}

Problem Solving Case Study

	void GetOneAmount( /*out*/ float& amount )   // Rainfall amount
	// for one month
	// Inputs one month's rainfall amount and, if necessary,
	// repeatedly prints an error message and inputs another
	// value if the value is negative
	// Postcondition:
	//     amount has been input (repeatedly, if necessary, along
	//     with output of an error message)
	//  && amount >= 0.0
	{
	do
	{
	cin >> amount;
	if (amount < 0.0)
	cout << "Amount cannot be negative. Enter again: ";
	} while (amount < 0.0);
	}