Thread: why does the value in for loop reset?

For each iteration of the outer loop, each time the code enters the inner loop, it will initialize i to 0.

You need to do two things:

1) You need to study loops more thoroughly.

2) you need to format your code better.

Code:

#include <stdio.h>

int main()
{
   int n = 0;   /* Initialize ALL local variables to 0, NULL, */   
   int i = 0;   /* or some other legitimate value! */

   for (n=1; n<=5; n++)
   {
      for (i=0; i<n; i++) 
      {
         printf("*");
      }
      printf("\n");
   }

   return 0;
}

Code:

Output:

*
**
***
****
*****

What output did you expect?

Originally Posted by rstanley

What output did you expect?

When i goes from 0 to 1, the condition for i<n is no longer met, when jumping out of the loop and changing n from 1 to 2 and then going into the inner loop, I was expecting i to still be 1 and not go back to 0. I did not know that the initialization statement goes back to its original state and I still do not know why it does that.

Originally Posted by mangekyou

When i goes from 0 to 1, the condition for i<n is no longer met, when jumping out of the loop and changing n from 1 to 2 and then going into the inner loop, I was expecting i to still be 1 and not go back to 0. I did not know that the initialization statement goes back to its original state and I still do not know why it does that.

That is the nature of how a for loop executes. For each iteration of the outer loop, the inner loop executes as a new statement.

Code:

for(initialization; condition; update)
{
...
}

"for (i=0; i<n; i++)"

Step 1) The first section, "i = 0", initialization ALWAYS executes, once, when the for loop starts.
Step 2) The second section, "i < n", the condition is tested, if true, the statements in the body of the for loop executes
Step 3) The third section, "i++", the loop variable is incremented
Step 4) The execution returns to Step 2, until the condition fails.

Again, please go back to a good book on the C Programming Language, and study the chapters on for(), while(), and do-while() loops!

Originally Posted by rstanley

That is the nature of how a for loop executes. For each iteration of the outer loop, the inner loop executes as a new statement.

Code:

for(initialization; condition; update)
{
...
}

"for (i=0; i<n; i++)"

Step 1) The first section, "i = 0", initialization ALWAYS executes, once, when the for loop starts.
Step 2) The second section, "i < n", the condition is tested, if true, the statements in the body of the for loop executes
Step 3) The third section, "i++", the loop variable is incremented
Step 4) The execution returns to Step 2, until the condition fails.

Again, please go back to a good book on the C Programming Language, and study the chapters on for(), while(), and do-while() loops!

I understand now, thanks for clearing it up. I just started studying C and Im definitely not done studying for loops. Thank you for your help