TP_7_C/exo2-base.c

   1 #include <stdio.h>
   2 #include <stdbool.h>
   3
   4 /** Display a prompt to the user then wait for an integer input. */
   5 int promptValue(const char* prompt) {
   6     printf("%s:\n", prompt);
   7     int result;
   8     scanf("%d", &result);
   9     return result;
  10 }
  11
  12 void displayMenuEntry(int index, const char* label) {
  13     printf("%d | %s\n", index, label);
  14 }
  15
  16 void displayMenu() {
  17     displayMenuEntry(1, "Addition");
  18     displayMenuEntry(2, "Substraction");
  19     displayMenuEntry(3, "Multiplication");
  20     displayMenuEntry(4, "Exit");
  21 }
  22
  23 /** Prompt the user for his operation choice.
  24  *
  25  * @return The selected operation. No invalid value can be returned.
  26  */
  27 int promptOperation() {
  28     displayMenu();
  29     int result;
  30
  31     do {
  32         result = promptValue("Choose an option");
  33
  34         if (result >= 1 && result <= 4) {
  35             break;
  36         }
  37
  38         puts("Please choose a valid option (1-4)");
  39     } while (true);
  40
  41     return result;
  42 }
  43
  44 int main() {
  45     int operation = promptOperation();
  46
  47     if (operation == 4) {
  48         return 0;
  49     }
  50
  51     int initialValue = promptValue("Initial value");
  52
  53     do {
  54         int nextValue = promptValue("Next value");
  55
  56         if (nextValue == 0) {
  57             break;
  58         }
  59
  60         switch (operation) {
  61         // Addition
  62         case 1:
  63             initialValue += nextValue;
  64             break;
  65
  66         // Substraction
  67         case 2:
  68             initialValue -= nextValue;
  69             break;
  70
  71         // Multiplication
  72         case 3:
  73             initialValue *= nextValue;
  74             break;
  75         }
  76
  77         printf("Result: %d\n", initialValue);
  78     } while (true);
  79 }