Question

Write a program that produces a bar chart showing the population growth of Prairieville, a small town in the Midwest, at 20-year intervals during the past 100 years. The program should read in the population figures for 1900, 1920, 1940, 1960, 1980, and 2000 from a file named People.txt. It is understood that the first value represents the population in 1900 (for example, 2,843), the second the population in 1920 and so on. For each year it should display the year, followed by at least one space followed by a bar consisting of one asterisk for each 1,000 people. (The program should round UP so that a population of 1 would generate one asterisk -- as would 1000, while a population of 1,001 would generate two, etc.)

Answer 1

Answer:

#include <iostream>

#include <fstream>

using namespace std;

int main()

{

ifstream Inputfile;

Inputfile.open("People.txt"); // Open file

if (!Inputfile) // Test for open errors

{

cout << "Error opening file.\n";

return 0;

}

int Pop; // Population

// Display Population Bar Chart Header

cout << "PRAIRIEVILLE POPULATION GROWTH\n"

<< "(each * represents 1000 people)\n";

for (int Year = 1; Year <= 6; Year++)

{ // One iteration per year

switch (Year)

{

case 1 : cout << "1900 ";

break;

case 2 : cout << "1920 ";

break;

case 3 : cout << "1940 ";

break;

case 4 : cout << "1960 ";

break;

case 5 : cout << "1980 ";

break;

case 6 : cout << "2000 ";

break;

}

Inputfile >> Pop; // Read from file

// calculate one per 1000 people

//cout<<"**"<<Pop<<endl;

while(Pop > 0)

{ // Display one asterisk per iteration

// One iteration per 1000 people

cout << "*";

Pop -= 1000;

}

cout << endl;

}

Inputfile.close(); // To close file

return 0;

}

Explanation: