Answer:
The ten numbers to be filled in the blanks are: 18, 7, 7, 11, 18, 36, 3, 8, 13, 50.
Step-by-step explanation:
keeps on going to the left node until node->left == NULL;
now at Node 18;
left = right = 0; hence condition is not satisfied
18 is printed first.
the value 18 is returned .
Then we reach at 4;
from there we move to 7;
just like 18, similar things happen with 7 and 7 is printed, the value 7 is returned.
Now coming to Node 4,
left = 0, right = 7 ; hence the condition is satisfied & res = 7; 7 is printed.
For Node 16, left = 7 ; right = 11(but for this we visit 11 first and 11 is printed)
for 16; condition is satisfied; res = 7 + 11 = 18 ; 18 is printed
Now for 5; left = right = 18; the condition is satisfied; so res = 18 + 18 = 36; 36 is printed
Next we visit Node 3; 3 is printed & 3 is returned
Then Node 8 ; 8 is printed & 8 is returned
for Node 13; left = 3, right = 8 ; condition is not satisfied, 13 is printed.
For Node 50; left = 36 right = 13 ; condition is not satisfied hence 50 is printed.
So the order of printing is 18 7 7 11 18 36 3 8 13 50.