Why does the function print zero?-CodePudding

The function should print numbers that are divisible by 3 in the given range. For example, if I give the range [3,9] it should print 3,6,9 but it prints 0,3,6,9. Why is that? How to fix it?

#include <stdio.h>
int main()
{
    printf("enter the value of a \n");
    int a;
    scanf("%d",&a);

    printf("enter the value of  b \n");
    int b;
    scanf("%d",&b);

   if(a>b)
    {
        printf("[%d,%d]\n",b ,a);


        for(  int b; b<=a; b=b 3)
        {
            printf("%d\n", b);
        }
    }

return 0;
}

CodePudding user response：

In this line

for(  int b; b<=a; b=b 3)
{
    printf("%d\n", b);
}

you are doing int b which you might know is who you declare variables, that means you are declaring a b inside the block of the loop, and since int's are initialized as 0 by default, your b is always going to be 0. Try removing that redeclaration and see if that fixes your problem

Yes, something like this is still valid:

for(; b<=a; b=b 3)
{
    printf("%d\n", b);
}