/* 

  Program: Sum & Average + Operator Precedence (U1)

  What it does:

    1) Reads three integers a, b, c.

    2) Computes sum = a + b + c and average = sum / 3.0 (note the .0 to avoid integer division).

    3) Evaluates a complex expression in two ways:

       - Raw   : a + b * c - 10 / 2   (multiplication/division happen before addition/subtraction)

       - Paren : ((a + b) * c) - (10 / 2) (parentheses change the evaluation order)

*/

#include <stdio.h>

int main(void) {

    int a, b, c;

    int sum;

    double avg;

    int expr_raw, expr_paren;

    printf("Enter three integers (a b c): ");

    if (scanf("%d %d %d", &a, &b, &c) != 3) {

        printf("Invalid input. Please enter exactly three integers.\n");

        return 0;

    }

    sum = a + b + c;

    avg = sum / 3.0;   /* 3.0 ensures floating-point division, not integer division */

    printf("Sum = %d\n", sum);

    printf("Average = %.2f\n", avg);

    /* Operator precedence demo: * and / before + and -, and left-to-right associativity */

    expr_raw   = a + b * c - 10 / 2;

    expr_paren = ((a + b) * c) - (10 / 2);

    printf("Expression (raw)   : a + b * c - 10 / 2 = %d\n", expr_raw);

    printf("Expression (paren) : ((a + b) * c) - (10 / 2) = %d\n", expr_paren);

    return 0;

}