Why am i getting 4 zeroes while concatenating a decimal n.o with string in this code,,

#1

my code;
https://ide.codingblocks.com/s/35256

question;
https://hack.codingblocks.com/contests/c/512/71

#2

https://ide.codingblocks.com/s/35256

You have posted wrong code link. Please be careful from next time.

#3

You can easily do this question by iteration, but it can be done by recursion as well. think over it.