c,loops,for-loop,macros,printf , Why is my C code printing out an extra line of rows?


Why is my C code printing out an extra line of rows?

Question:

Tag: c,loops,for-loop,macros,printf
#include <stdio.h>

#define rows 500 //can define rows as any number

int main()
{
    int i,j;

    for(i=0;i<=rows;++i)
    {
        for(j=0;j<(2*i+1);++j)
        {
           printf("* ");
        }
        printf("\n");
    }
    return 0;
}

So here is my code, what it does is it prints the number of rows set by #define and creates a right angle triangle. But whatever I set that number to it always prints out 1 extra row of stars, and I can't figure out why.

I know I can set it as i=0;i<500;i++ and just forget about the #define statement but I'm trying to make it work with it.

Any help would be great.


Answer:

There is no issue with the #define, there is one issue with the conditional statement in the for loop.

I believe, you'er overlooking the <= operator. You need to have only < operator. Change

 for(i=0;i<=rows;++i)

to

for(i=0;i<rows;++i)

That said, the recommended signature of main() is int main(void).


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