If Statements

Conditions

You have already learned that C supports the usual logical conditions from mathematics:

• Less than: a < b
• Less than or equal to: a <= b
• Greater than: a > b
• Greater than or equal to: a >= b
• Equal to: a == b
• Not Equal to: a != b

---

Project 1

#include <stdio.h>

int main()
{
    int a, b;

    // Enter number
    printf("Enter first number : ");
    scanf("%d", &a);
    printf("Enter second number : ");
    scanf("%d", &b);

    // check function
    if (a > b){
        printf("\nFirst number > Second number --> sub : %d\n", a - b);
    }
    else if (a < b){
        printf("\nFirst number < Second number --> add : %d\n", a + b);
    }
    else{
        printf("\nFirst number = Second number --> mul : %d\n", a * b);
    }
}

Output :

Enter first number : 5
Enter second number : 99

First number < Second number --> add : 104

---

Project 2

#include <stdio.h>

int main()
{
    int price;

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

    int tax = price * 0.07;
    int sum = price + tax;
    // check function
    if (price > 5000)
    {
        printf("\nYou must pay tax : %d ", tax);
        printf("\nYou pay : %d\n", sum);
    }
    else
    {
        printf("\nYou don't pay taxes.");
        printf("\nYou pay : %d\n", price);
    }
}

Output :

Enter your price : 1000

You don't pay taxes.
You pay : 1000

---

Project 3

#include <stdio.h>

int main()
{
    float amount;

    printf("Enter number of amount : ");
    scanf("%f", &amount);

    // check function
    if (amount < 500)
    {
        printf("\nCost : %.2f\n", amount * 8.5);
    }
    else if ((amount >= 500) && (amount <= 999))
    {
        printf("\nCost : %.2f\n",amount * 8.0);
    }
    else
    {
        printf("\nCost : %.2f\n", amount * 7.5);
    }
}

Output :

Enter number of amount : 10000

Cost : 75000.00

---

Project 4

#include <stdio.h>

void main()
{
    char letter;

    printf("Enter your letter : ");
    scanf("%c", &letter);

    switch (letter)
    {
        case 'a' :
        case 'A' :
        printf("\nYes, It is vowel.\n");
        break;

        case 'e':
        case 'E' :
        printf("\nYes, It is vowel.\n");
        break;

        case 'i':
        case 'I' :
        printf("\nYes, It is vowel.\n");
        break;

        case 'o':
        case 'O' :
        printf("\nYes, It is vowel.\n");
        break;

        case 'u':
        case 'U' :
        printf("\nYes, It is vowel.\n");
        break;

        default:
        printf("\nNO, It is alphabet.\n");
    }
}

Output :

Enter your letter : e

Yes, It is vowel.