How to end the do while loop on my demand? [closed] - c

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The following code generates Fibonacci numbers using a Do While function, instead of specifying the exact number of the exit condition while (b < 144) I want to be less precise and just make it not to show numbers that are greater that an specific value (let's say 150).
how can I do it?
please note that I'm only know basic functions.
int main()
{
int a;
int b = 0;
int c = 1;
printf("the fibonacci numbers up to 144 are:\n");
printf("%i", b);
do
{
a = c+b;
printf("\n%i", a);
c = a+b;
printf("\n%i", c);
b = c+a;
printf("\n%i", b);
}
while (b < 144);
return 0;
}

Answer 1

I'm not sure what do you intend for "on demand". If you mean on demand by code you could use an internal if and if condition is true then exit the loop with break command. Example extracted by linked URL:
for (i = 0; i < 5; i++) {
if (string[i] == '\0')
break;
length++;
}
If on demand means "as soon you want to stop it" then use CTRL+C sice you are in a console application.
Edit: Since your function already exit on command, you probably want to know "how to read the standard input in a console application?"
Answer: Using the scanf function (here an example):
#include <stdio.h>
int main() {
int n;
printf("Insert the value of N: ");
scanf ("%d",&n);
printf("N*N is equal to: %d\n", n*n);
getch();
}

Answer 2

You might want to use somthing like that :
while (a < MAX_VALUE && b < MAX_VALUE && c < MAX_VALUE)
Where MAX_VALUE is a preprocessor macro at the start of your program after the includes (http://gcc.gnu.org/onlinedocs/cpp/Macros.html#Macros), for example :
#define MAX_VALUE 100000

Answer 3

You can enter the limit for the number up to which do you want the series.
int n;
printf("Enter the limit: ");
scanf("%d", &n);
printf("\nthe fibonacci numbers up to %d are:\n", n);
printf("%i", b);
do
{
...
n--;
}
while (n);

Answer 4

Solved it: added a user specified limit and an if statement to check after each addition:
thanks for the help!
float lim;
int a;
int b = 0;
int c = 1;
printf("The following program generates Fibonacci numbers up to a specified value\n");
printf("Please enter a value of your choise:");
scanf("%f4", &lim);
printf("the fibonacci numbers up to %.2f are:\n", lim);
printf("%i", b);
do
{
a = c+b;
c = a+b;
b = c+a;
if ( a >= lim) break;
printf("\n%i", a);
if ( c >= lim) break;
printf("\n%i", c);
if ( b >= lim) break;
printf("\n%i", b);
}
while(b <= lim);