Week 02 Laboratory Sample Solutions

// Show the dice range of a set of dice as well
// as their average roll
// Created 7/6/2019 by Marc Chee (marc.chee@unsw.edu.au)
// as a lab challenge

// Note this program doesn't check whether
// the scanf call successfully reads a number.
// This is good practice but was not requested in the lab exercise
// because this isn't covered until later in the course.

#include <stdio.h>

int main(void) {
    int diceSize;
    int numDice;
    int lowest;
    int highest;
    double average;
    
    // scan in dice stats
    printf("Enter the number of sides on your dice: ");
    scanf("%d", &diceSize);
    printf("Enter the number of dice being rolled: ");
    scanf("%d", &numDice);

    // calculate lowest and highest values
    lowest = numDice;
    highest = numDice * diceSize;
    
    // calculate average. The 2.0 makes the result a double
    average = (lowest + highest) / 2.0;
    
    if (diceSize <= 0 || highest <= 0) {
        printf("These dice will not produce a range.\n");
    } else {
        printf("Your dice range is %d to %d.\n", lowest, highest);
        printf("The average value is %lf\n", average);
    }

    return 0;
}

// Word Addition -- a sample solution.
// Add two numbers and print them out, as words.

#include <stdio.h>

int main(void) {
    int num1, num2;
    printf("Please enter two integers: ");
    scanf("%d %d", &num1, &num2);
    int sum = num1 + num2;

    // First, deal with num1.
    // Is it between -10 and 10?
    if (num1 >= -10 && num1 <= 10) {
        // Is it negative?
        if (num1 < 0) {
            printf("negative ");
            num1 *= -1;
        }
        // Print out whatever the digit is.
        if (num1 == 0) {
            printf("zero");
        }
        if (num1 == 1) {
            printf("one");
        }
        if (num1 == 2) {
            printf("two");
        }
        if (num1 == 3) {
            printf("three");
        }
        if (num1 == 4) {
            printf("four");
        }
        if (num1 == 5) {
            printf("five");
        }
        if (num1 == 6) {
            printf("six");
        }
        if (num1 == 7) {
            printf("seven");
        }
        if (num1 == 8) {
            printf("eight");
        }
        if (num1 == 9) {
            printf("nine");
        }
        if (num1 == 10) {
            printf("ten");
        }
    } else {
        // It wasn't between -10 and 10, so print out the number as is.
        printf("%d", num1);
    }

    // Now, print out the plus sign...
    printf(" + ");

    // Now, deal with num2
    // Is it between -10 and 10?
    if (num2 >= -10 && num2 <= 10) {
        // Is it negative?
        if (num2 < 0) {
            printf("negative ");
            num2 *= -1;
        }
        // Print out whatever the digit is
        if (num2 == 0) {
            printf("zero");
        }
        if (num2 == 1) {
            printf("one");
        }
        if (num2 == 2) {
            printf("two");
        }
        if (num2 == 3) {
            printf("three");
        }
        if (num2 == 4) {
            printf("four");
        }
        if (num2 == 5) {
            printf("five");
        }
        if (num2 == 6) {
            printf("six");
        }
        if (num2 == 7) {
            printf("seven");
        }
        if (num2 == 8) {
            printf("eight");
        }
        if (num2 == 9) {
            printf("nine");
        }
        if (num2 == 10) {
            printf("ten");
        }
    } else {
        // It wasn't between -10 and 10, so print out the number as is.
        printf("%d", num2);
    }

    // Now, print the equals sign.
    printf(" = ");


    // Now, deal with the sum
    // Is it between -10 and 10?
    if (sum >= -10 && sum <= 10) {
        // Is it negative?
        if (sum < 0) {
            printf("negative ");
            sum *= -1;
        }
        // Print out whatever the digit is.
        if (sum == 0) {
            printf("zero\n");
        }
        if (sum == 1) {
            printf("one\n");
        }
        if (sum == 2) {
            printf("two\n");
        }
        if (sum == 3) {
            printf("three\n");
        }
        if (sum == 4) {
            printf("four\n");
        }
        if (sum == 5) {
            printf("five\n");
        }
        if (sum == 6) {
            printf("six\n");
        }
        if (sum == 7) {
            printf("seven\n");
        }
        if (sum == 8) {
            printf("eight\n");
        }
        if (sum == 9) {
            printf("nine\n");
        }
        if (sum == 10) {
            printf("ten\n");
        }
    } else {
        // It wasn't between -10 and 10, so print out the number as is.
        printf("%d\n", sum);
    }

    return 0;
}

// Compute Easter Sunday date
// Modified 3/3/2019 by Andrew Taylor (andrewt@unsw.edu.au)
// as a lab example for COMP1511

// code for Butcher's Formula copied from
// http://smart.net/~mmontes/nature1876.html

// Note this program doesn't check whether
// the scanf call successfully reads a number.
// This is good practice but was not requested in the lab exercise
// because this isn't covered until later in COMP1511.

#include <stdio.h>

int main(void) {
    int a, b, c, d, e, f, g, h, i, k, l, m, p;
    int year, month, date;

    printf("Enter year: ");
    scanf("%d", &year);

    a = year % 19;
    b = year / 100;
    c = year % 100;
    d = b / 4;
    e = b % 4;
    f = (b + 8) / 25;
    g = (b - f + 1) / 3;
    h = (19 * a + b - d - g + 15) % 30;
    i = c / 4;
    k = c % 4;
    l = (32 + 2 * e + 2 * i - h - k) % 7;
    m = (a + 11 * h + 22 * l) / 451;
    month = (h + l - 7 * m + 114) / 31;  //  [3=March, 4=April]
    p = (h + l - 7 * m + 114) % 31;
    date = p + 1;  // (date in Easter Month)

    printf("Easter is ");

    if (month == 3) {
        printf("March");
    } else {
        printf("April");
    }

    printf(" %d in %d.\n", date, year);

    return 0;
}