Practice Exercises

Topics: exercises
Exercise 1: Medical Staff Profile

Create a program that:

  • Stores a healthcare worker’s basic information (name, age, department)
  • Calculates their year of birth
  • Creates a formatted introduction message
name         <- "Dr. Maria Santos"
age          <- 35
department   <- "Pediatrics"
current_year <- 2026

birth_year <- current_year - age
intro <- sprintf("Hi! I'm %s, a %d-year-old physician from the %s department, born in %d.",
                 name, age, department, birth_year)

print(intro)
Exercise 2: Medication Inventory Manager

Create a program that:

  • Starts with a vector of medications
  • Adds new medications to the vector
  • Removes one discontinued medication
  • Prints the final list with numbering
med_inventory <- c("Paracetamol", "Amoxicillin", "Ibuprofen", "Metformin", "Amlodipine")
med_inventory <- c(med_inventory, "Cefalexin", "Losartan")   # Add new medications
med_inventory <- med_inventory[med_inventory != "Ibuprofen"]   # Remove discontinued

cat("Medication Inventory:\n")
for (i in seq_along(med_inventory)) {
  cat(i, ". ", med_inventory[i], "\n", sep = "")
}
Exercise 3: Grade Calculator

Create a program that:

  • Stores student information in a list
  • Calculates the average grade
  • Determines letter grade based on average
  • Prints a formatted report
student <- list(
  name   = "Alice",
  grades = c(85, 92, 78, 96, 88)
)

average <- mean(student$grades)

if (average >= 90) {
  letter_grade <- "A"
} else if (average >= 80) {
  letter_grade <- "B"
} else if (average >= 70) {
  letter_grade <- "C"
} else if (average >= 60) {
  letter_grade <- "D"
} else {
  letter_grade <- "F"
}

cat("Student:", student$name, "\n")
cat("Grades:", paste(student$grades, collapse = ", "), "\n")
cat(sprintf("Average: %.1f\n", average))
cat("Letter Grade:", letter_grade, "\n")
Exercise 4: Patient Vital Score Calculator

Create a program that:

  • Stores a patient’s recorded vital scores (e.g., from multiple checkups)
  • Calculates the average
  • Categorizes the patient’s overall condition
patient <- list(
  name      = "Juan Dela Cruz",
  bp_scores = c(120, 130, 125, 128, 118)
)

average <- mean(patient$bp_scores)

if (average >= 140) {
  condition <- "Hypertensive"
} else if (average >= 120) {
  condition <- "Prehypertensive"
} else {
  condition <- "Normal"
}

cat("Patient:", patient$name, "\n")
cat("BP Readings:", paste(patient$bp_scores, collapse = ", "), "\n")
cat(sprintf("Average BP: %.1f\n", average))
cat("Condition:", condition, "\n")
Exercise 5: Health Record Access Validator

Create a function that validates a hospital staff’s password before they can access patient records:

  • At least 8 characters long
  • Contains at least one number
  • Contains at least one uppercase letter
validate_password <- function(password) {
  if (nchar(password) < 8) {
    return(list(valid = FALSE, message = "Password must be at least 8 characters long"))
  }

  has_number <- grepl("[0-9]", password)
  has_upper  <- grepl("[A-Z]", password)

  if (!has_number) {
    return(list(valid = FALSE, message = "Password must contain at least one number"))
  }

  if (!has_upper) {
    return(list(valid = FALSE, message = "Password must contain at least one uppercase letter"))
  }

  return(list(valid = TRUE, message = "Password is valid"))
}

# Test the function
test_passwords <- c("weak", "StrongPass1", "nodigits", "NONUMBERS")

for (pwd in test_passwords) {
  result <- validate_password(pwd)
  cat(sprintf("'%s': %s\n", pwd, result$message))
}
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