How to use if else statement?

EXERCISE 3
Write a program to calculate a salary of a salesperson based on the unit of items sold.
 Get the staff name, salary and the units sold.
 Get the bonus percentage for sales as shown in the following table, based on the units sold.
o The bonus amount is the bonus percentage of the salary.
 Calculate the total salary for the salesperson.
 Display the name, salary, units sold, bonus percentage, bonus amount and total salary.
 Design your own format of an appropriate output for this program.


Hello guys. I need help to solve this kind of question. I have done my own programming but it seems to have some errors. I have tried and searched all the possible solutions to solve this matter but the outcomes are still the same. I would appreciate if someone can help me to solve this kind of problem. Thanks in advance.


Below is the code that I have done. I hope you guys can fix it or give me a clue/hint on how to solve this question.

Code:

#include <stdio.h>
#include <string.h>


void main()
{
    int unit;
    float salary;
    char staff[20] , bonus;


    printf("\n-------------------------------------");
    printf("\n               BONUS                 ");
    printf("\n-------------------------------------");


    printf("\nEnter the staff name : ");
    gets (staff);
    printf("\nEnter the salary : RM ");
    scanf("%f", &salary);
    printf("\nEnter the units sold : ");
    scanf("%d", &unit);


    salary = unit * bonus;


    if (unit > 100 || unit < 200){
    strcpy(bonus, "0.02");
    }
    else if (unit > 201 || unit < 300){
    strcpy(bonus, "0.04");
    }
    else if (unit > 300){
    strcpy(bonus, "0.06");
    }


    salary = unit * bonus;


    printf("\nStaff name : %s ", staff);
    printf("\nSalary : %f ", salary);
    printf("\nUnits Sold : %d ", unit);
    printf("\nBonus Percentage : %.2f ", bonus);
    printf("\nBonus Amount : ");
    printf("\nTotal Salary : RM");


    return 0;
}

Why is bonus a char? Seems to me a bonus should be a float, probably. You're trying to strcpy strings like "0.02" into bonus (by the way strcpy only works into strings, not single chars!)... wouldn't that be easier as [b]bonus = 0.02;[b]? This way the multiplication unit * bonus might actually work.

You seem to be printing bonus as a float, in fact: %.2f.

Your test conditions have some edge cases they don't handle. For example, if precisely 200 or 201 is entered, none of the bonuses will apply. Try <= and >=. Also it should probably be and's, not or's: every single number is either greater than 100 OR less than 200!

Remember you can avoid redundant boolean expressions by turning

Code:

if(x >= 20 && x <= 30) ...
else if(x >= 10 && x <= 20) ...
else if(x >= 0 && x <= 10)

into (say)

Code:

if(x >= 20) ...
else if(x >= 10) ...
else if(x >= 0)

or some such. (With an extra check for > 30 if you needed to.)

Other comments:

• You should use int main rather than void main. SourceForge.net: Void main - cpwiki
• gets() is dangerous... you should avoid it too. SourceForge.net: Gets - cpwiki

I've edited the codes but now I keep getting errors like "expected expression before '>' token".

I thought this is an expression

Code:

if (unit => 100 && unit <= 200)

By the way, can I know what does this "[b] means?

Code:

[b]bonus = 0.02;[b]

This is the code I've edited so far.

Code:

#include <stdio.h>


int main()
{
    int unit;
    float salary, bonus;
    char staff;


    printf("\n-------------------------------------");
    printf("\n               BONUS                 ");
    printf("\n-------------------------------------");


    printf("\nEnter the staff name : ");
    scanf("%c", &staff);
    printf("\nEnter the salary : RM ");
    scanf("%f", &salary);
    printf("\nEnter the units sold : ");
    scanf("%d", &unit);


    salary = unit * bonus;


    if (unit => 100 && unit <= 200) {
    bonus =0.02;
    }
    else if (unit => 201 && unit <= 300){
    bonus =0.04;
    }
    else (unit => 300){
    bonus =0.06;
    }


    salary = unit * bonus;


    printf("\nStaff name : %c ", staff);
    printf("\nSalary : %f ", salary);
    printf("\nUnits Sold : %d ", unit);
    printf("\nBonus Percentage : %.2f ", bonus);
    printf("\nBonus Amount : ");
    printf("\nTotal Salary : RM ");


    return 0;
}

=> should be >=

And else has no condition.

In the if...else if...else if... construction the idea is that the final "else" can be used to handle "exceptional" cases. For example

Code:

    if (unit => 100 && unit <= 200) {
        bonus =0.02;
    }
    else if (unit => 201 && unit <= 300){
        bonus =0.04;
    }
    else if (unit => 300){
        bonus =0.06;
    }
    else {
        printf("Invalid unit entered. Program will exit.\n");
        exit(127);
    }

That's just one possibility

And if unit is less than 100, what is bonus then?

What's the use of line 24 when you have line 38?