why only the succeeding value adds up???

hi guys i wonder what i am messing in my program,

Code:

---

main()
{
clrscr();

int order;
char ans;
int total;

printf("Good Day Ma'am/Sir !!!\n\n");


printf("\t1. Regular Yum \t\t\t\t\tP25.00\n");
printf("\t2. One Piece Chicken Joy\t\t\tP55.00\n");
printf("\t3. One Piece Burger Steak \t\t\tP45.00\n");
printf("\t4. Spaghetti\t\t\t\t\tP35.00\n");
printf("\t5. Regular Yum with Spaghetti\t\t\tP50.00\n");
printf("\t6. One Piece Burger Steak with Spaghetti\tP70.00\n");
printf("\t7. One Piece Chicken Joy with Spaghetti\t\tP80.00\n");
printf("\t8. Softdrinks\t\t\t\t\tP15.00\n\n\n");

do
{
printf("\nPlease select your order:  ");
scanf("%d",&order);
total=0;

if(order==1){
      total=25.00;
      }
else if (order==2){
        total=55.00;
        }
else if(order==3){
        total=45.00;
        }
else if (order==4){
        total=35.00;
        }
else if(order==5){
        total=50.00;
        }
else if (order==6){
        total=70.00;
        }
else if(order==7){
        total=80.00;
        }
else if(order==8){
        total=15.00;
        }

total+=total;


printf("\nWould you like to order again?(y/n)  ");
scanf(" %c",&ans);

}
while(ans=='y');

printf("\nYour total order is P%d.",total);

getch();
return(0);
}

---

when my program displays the total, only the second orders adds up or the succeeding order adds up?

am i messing something???

You can't have two variables with the same name -- you have an order total, which you call "total", and you have a total-for-the-whole-program, which you call "total". Needless to say, the compiler treats these as the same variable.

[Never mind]

Your analyzis of what goes wrong is probably incorrect - you are overwriting the "total" every time you select something, so if you order number 1 three times over, it will still end up with 2 times "total += total", where total has been set to 25 in the first case.

[You may want to consider using "switch" instead of if-else to determine the choice].

--
Mats

you mean like this???

Code:

---


main()
{
clrscr();

int order;
char ans;
int total;
int sum;

printf("Good Day Ma'am/Sir !!!\n\n");
printf("Welcome to Jollibee ...\n\n\n");

printf("\t1. Regular Yum \t\t\t\t\tP25.00\n");
printf("\t2. One Piece Chicken Joy\t\t\tP55.00\n");
printf("\t3. One Piece Burger Steak \t\t\tP45.00\n");
printf("\t4. Spaghetti\t\t\t\t\tP35.00\n");
printf("\t5. Regular Yum with Spaghetti\t\t\tP50.00\n");
printf("\t6. One Piece Burger Steak with Spaghetti\tP70.00\n");
printf("\t7. One Piece Chicken Joy with Spaghetti\t\tP80.00\n");
printf("\t8. Softdrinks\t\t\t\t\tP15.00\n\n\n");



do
{
printf("\nPlease select your order:  ");
scanf("%d",&order);
total=0;

if(order==1){
      total=25.00;
      }
else if (order==2){
        total=55.00;
        }
else if(order==3){
        total=45.00;
        }
else if (order==4){
        total=35.00;
        }
else if(order==5){
        total=50.00;
        }
else if (order==6){
        total=70.00;
        }
else if(order==7){
        total=80.00;
        }
else if(order==8){
        total=15.00;
        }

sum+=total;


printf("\nWould you like to order again?(y/n)  ");
scanf(" %c",&ans);

}
while(ans=='y');

printf("\nYour total order is P%d.",sum);

getch();
return(0);
}

---

That looks better. Does it work? [You may find that you get a strange result - what is sum before you start adding orders together?]

--
Mats

You're nearly there -- you need to start sum off at 0.

It would be a lot easier to follow with some decent indentation.

Code:

---

main()
{
clrscr();

int order;
char ans;
int total;
int sum;

printf("Good Day Ma'am/Sir !!!\n\n");


printf("\t1. Regular Yum \t\t\t\t\tP25.00\n");
printf("\t2. One Piece Chicken Joy\t\t\tP55.00\n");
printf("\t3. One Piece Burger Steak \t\t\tP45.00\n");
printf("\t4. Spaghetti\t\t\t\t\tP35.00\n");
printf("\t5. Regular Yum with Spaghetti\t\t\tP50.00\n");
printf("\t6. One Piece Burger Steak with Spaghetti\tP70.00\n");
printf("\t7. One Piece Chicken Joy with Spaghetti\t\tP80.00\n");
printf("\t8. Softdrinks\t\t\t\t\tP15.00\n\n\n");



do
{
printf("\nPlease select your order:  ");
scanf("%d",&order);
total=0;

switch(order){
case 1:
      total=25.00;

case 2:
        total=55.00;

case 3:
        total=45.00;

case 4:
        total=35.00;

case 5:
        total=50.00;

case 6:
        total=70.00;

case 7:
        total=80.00;

case 8:
        total=15.00;
}


sum+=total;


printf("\nWould you like to order again?(y/n)  ");
scanf(" %c",&ans);

}
while(ans=='y');

printf("\nYour total order is P%d.",sum);

getch();
return(0);
}

---

now it goes more crazy this time T_T

You need breaks when you use a switch.

And your sum is still undefined... (Yes, you've declared the variable, but never set it to an initial value).

Mats

Code:

---


#include<stdio.h>
#include<conio.h>

main()
{
clrscr();

int order;
char ans;
int total;
int sum;

printf("Good Day Ma'am/Sir !!!\n\n");


printf("\t1. Regular Yum \t\t\t\t\tP25.00\n");
printf("\t2. One Piece Chicken Joy\t\t\tP55.00\n");
printf("\t3. One Piece Burger Steak \t\t\tP45.00\n");
printf("\t4. Spaghetti\t\t\t\t\tP35.00\n");
printf("\t5. Regular Yum with Spaghetti\t\t\tP50.00\n");
printf("\t6. One Piece Burger Steak with Spaghetti\tP70.00\n");
printf("\t7. One Piece Chicken Joy with Spaghetti\t\tP80.00\n");
printf("\t8. Softdrinks\t\t\t\t\tP15.00\n\n\n");



do
{
printf("\nPlease select your order:  ");
scanf("%d",&order);
total=0;

switch(order){
case 1:
      total=25.00;
      break;

case 2:
        total=55.00;
        break;
case 3:
        total=45.00;
        break;
case 4:
        total=35.00;
        break;
case 5:
        total=50.00;
        break;
case 6:
        total=70.00;
        break;
case 7:
        total=80.00;
        break;
case 8:
        total=15.00;
        break;
}


sum+=total;


printf("\nWould you like to order again?(y/n)  ");
scanf(" %c",&ans);

}
while(ans=='y');

printf("\nYour total order is P%d.",sum);

getch();
return(0);
}

---

ok, i set the value for the SUM! please help here, i change some of the values and followed what you said, still im getting the wrong answers!

Code:

---


#include<stdio.h>
#include<conio.h>

main()
{
clrscr();

int order;
char ans;
int total=0;
int sum;

printf("Good Day Ma'am/Sir !!!\n\n");


printf("\t1. Regular Yum \t\t\t\t\tP25.00\n");
printf("\t2. One Piece Chicken Joy\t\t\tP55.00\n");
printf("\t3. One Piece Burger Steak \t\t\tP45.00\n");
printf("\t4. Spaghetti\t\t\t\t\tP35.00\n");
printf("\t5. Regular Yum with Spaghetti\t\t\tP50.00\n");
printf("\t6. One Piece Burger Steak with Spaghetti\tP70.00\n");
printf("\t7. One Piece Chicken Joy with Spaghetti\t\tP80.00\n");
printf("\t8. Softdrinks\t\t\t\t\tP15.00\n\n\n");



do
{
printf("\nPlease select your order:  ");
scanf("%d",&order);
sum=0;

switch(order){
case 1:
      total=25.00;
      break;

case 2:
        total=55.00;
        break;
case 3:
        total=45.00;
        break;
case 4:
        total=35.00;
        break;
case 5:
        total=50.00;
        break;
case 6:
        total=70.00;
        break;
case 7:
        total=80.00;
        break;
case 8:
        total=15.00;
        break;
}


sum+=total;

printf("\nWould you like to order again?(y/n)  ");
scanf(" %c",&ans);

}
while(ans=='y');

printf("\nYour total order is P%d.",sum);

getch();
return(0);
}

---

You probably don't want to set the value of sum to zero in EACH iteration of the loop...

--
Mats

yow thnx! i've set the SUM to the upper part of the program and works like charm...


thnx a lot to you guys,

but one more question, can i get it working by not using the switch ?

instead i will use the if else command?

more power ....!

yeah, but why does that mean more power?

you could replace the whole switch with a small array (no more conditionals):

Code:

---

  int total[]={0/*unused*/,25,55,45,...};
  printf(...)
  scanf("%u",&order);
  sum+=total[order%the_appropriate_value];

---

Quote:

---

Originally Posted by root4

you could replace the whole switch with a small array (no more conditionals):

Code:

---

  int total[]={0/*unused*/,25,55,45,...};
  printf(...)
  scanf("%u",&order);
  sum+=total[order%the_appropriate_value];

---

---

Although it probably is a good idea to range-check the values.

--
Mats

You CAN of course use if/else instead of switch/case - but consider what the compiler does if you have a value 8 for this:

Code:

---

if(order==1){
      total=25.00;
      }
else if (order==2){
        total=55.00;
        }
else if(order==3){
        total=45.00;
        }
else if (order==4){
        total=35.00;
        }
else if(order==5){
        total=50.00;
        }
else if (order==6){
        total=70.00;
        }
else if(order==7){
        total=80.00;
        }
else if(order==8){
        total=15.00;
        }

---

Unless it figures out that it's a "switch in disguise", it will compare down the chain until it finds the one that matches. In a switch/case block, the compiler will (most of the time) generate a jump-table, which means that no matter how many variants it is, there will be a O(1) type, rather than O(n) that the if/else version does.

Note that reasonably modern/clever compilers, such as gcc 3.4 can not figure out that the above is a "switch/case in disguise". I just tried out the above code as a if/else, and as a switch/case, and for the average case, the code is simply shorter and better for the switch/case statement.

But if it's part of your assignment to use if-else, then do so.

--
Mats