Can anyone explain this code snippet too why 50 is the answer?

Question

#include <stdio.h>
void find(int x){
static int i = 10, y = 0;
y = y+i;
for(i;i>0;i=i-10){
if (x!=0)
find(x-1);
else
printf("%d",y);
}
}
int main() {
find(4);
return 0;
}

Answer 1

It is a recursive method. Recursion means that this method calls itself.

find(4):
i = 10
y = 10
x = 4

x != 0 -> call find(3)

find(3):
i = 10
y = 20
x = 3

x != 0 -> call find(2)
find(2) -> y gets 30
find(1) -> y gets 40
find(0) -> y gets 50 -> x == 0
-> print y

I am only wondering about the loop. It does nothing with i and I think the code would also work without this loop.

Answer 2

#include <stdio.h>
void find(int x){
static int i = 10, y = 0;
y = y+i;
for(i;i>0;i=i-10){
if (x!=0)
find(x-1);
else
printf("%d",y);
printf("\n%d", i);
}
}
int main() {
find(4);
return 0;
}
When I print the value of I inside the function it will give 10, 0, -10, -20, -30

Answer 3

~ swim ~ Thanks. Now I understand it.

Answer 4

for(i;i>0;i=i-10){
printf("\n%d", i); <-- here
if (x!=0)
find(x-1);
else
printf("%d",y);
}

My fault. I mean at the beginning of the loop before you call the function again.

Answer 5

Denise Roßberg
Don't u think I value should change to 10,0,-10,-20.. because of static i. Does static doesn't affect it??

Answer 6

Preity
I can't explain why but i is always 10. You can add a print statement inside the loop.