Functions Part 2

Video

Key Takeways

Video Addendum

Assignment

• For each code sample (0 to 2):
  1. Walk through the memory table for at least 2 different inputs.
  2. Write down what you think each sample does (in complete sentences).
  3. Execute the code in a repl to validate your assumption. What was wrong / right about your step 2?
  4. Do you see room for improvement in this code? If so, create a new repl with all of your improvements.
• For each code sample (3 to 4):
  1. Describe what you think is wrong with the code (This means write it down in complete sentences!).
  2. Confirm your hypothesis by building a memory table.
  3. Double check your work by trying to run the code in a new Repl for each example.
  4. In that same repl, try and make the relevant fixes until you’re satisfied.
• For your updated calculator from lesson 05, are there any places you can use functions with inputs?
  • If so, create a new repl that does the exact same task but uses functions. Write down why you created the functions you did.
  • If not, describe why you aren’t able to use functions.

Code Samples

Sample 0

#include <iostream>

int Function2(int a) {
    a = a + 1;
    return a * a;
}

int Function1() {
    int n;
    std::cin >> n;
    return n;
}

int main() {
    int a = Function1();
    int b = Function2(a);
    std::cout << "A square with size bigger than " << a << std::endl;
    std::cout << "Has an area of size at least " << b << std::endl;
    return 0;
}

Sample 1

#include <iostream>

int GetUserInput() {
    std::cout << "Enter a number: ";
    int n;
    std::cin >> n;
    return n;
}

int FunctionP(int a, int b) {
    return a * b;
}

int main() {
    int c = GetUserInput();
    int d = GetUserInput();
    int a = FunctionP(c, d);
    std::cout << "Area " << c << "x" << d << " = " << a << std::endl;
    return 0;
}

Sample 2

#include <iostream>

int GetUserInput() {
    std::cout << "Enter a number: ";
    int n;
    std::cin >> n;
    return n;
}

char FunctionC(int c) {
    if (c == 0) {
        return 'a';
    }
    if (c == 1) {
        return 'e';
    }
    if (c == 2) {
        return 'i';
    }
    if (c == 3) {
        return 'o';
    }
    if (c == 4) {
        return 'u';
    }
    return ' ';
}

int FunctionD(int a) {
    if (a == 0) {
        std::cout << "th";
    }
    if (a == 1) {
        std::cout << "st";
    }
    if (a == 2) {
        std::cout << "th";
    }
    if (a == 3) {
        std::cout << "rd";
    }
    if (a == 4) {
        std::cout << "th";
    }

    return 0;
}

bool FunctionZ(int z) {
    if (z < 0) {
        return true;
    }

    if (z >= 5) {
        return true;
    }

    return false;
}

int main() {
    int a = GetUserInput();
    bool r = FunctionZ(a);
    if (r) {
        std::cout << "Sorry bad number. Try again." << std::endl;
        return 1;
    }

    char l = FunctionC(a);

    std::cout << "The " << a;
    a = FunctionD(a);
    std::cout << " vowel is " << l << "." << std::endl;
    return 0;
}

Sample 3

#include <iostream>

int functionz() {
    std::cout << "Enter a number: ";
    int n;
    std::cin >> n;
    return n;
}

int function_a(int a, int b) {
    if (a > b) {
        return b;
    }
    return a;
}

int main() {
    int z = functionZ();
    int b = functionZ()
    int c = function_a(b);
    std::cout << "The bigger number between : " << z << "  " << b << " is " << c << "." << std::endl;
    return 0;
}

Sample 4

#include <iostream>

float A(float p) {
    return pi * 4.0 / 3.0 * p * p * p;
}

int main() {
    float A = GetUserInput();
    float b = A(A);
    std::cout << "Volume of sphere with radius " << A << " is " << b << "." << std::endl;
    return 0;
}

End of Assignment Checklist

• I finished all the assignments.
• I shared my assignments with others.
• I provided feedback for assignments of at least 2 others.
• I addressed the feedback from others and thanked them for the review.