How to avoid retaining string values in C in function calls

Question

Edit: solution was to use strdup()

I have re-asked my question. How to create to a new string to use as a key everytime I call a function?

I want to a fresh variable char[] newer everytime my function is called. The reason is because I set my key as newer in a global hashmap. I don't want keys being modified everytime I call the function and modify newer.

#include <stdio.h>
#include <string.h>
void new(){
    char  newer[45];
    printf("%s
", newer);
    strncat(newer,"hi",1235);
}
int main()
{
    int i = 0;
    for (i = 0; i < 6; i++){
        new();
    }
}

My current output is

hi                                                                                                                                            
hihi                                                                                                                                          
hihihi                                                                                                                                        
hihihihi                                                                                                                                      
hihihihihi  

but I want it to be

hi
hi
hi
hi
hi

Edit: I forgot to mention the purpose of my code. I'm not able to post the code completely since it's a school project. Basically let's say I have a global hashmap that takes (key,value) pairs. Everytime I call the new() it should add a new entry to the hashmap. For example I have a function add which is supposed to add (key = newer, value = "something") to the global hashmap. I want hashmap = { key1="hi":value1="stuff",key2="hihi":value2=stuff2"} after 2 calls to the function. For some reason my hashmap ends up being {key1="hi:value1="stuff"} after 1 call and then {key1="hihi":value1="stuff",key2="hihi":value2="stuff2"} after 2 calls. The reason is because the key1 = newer and key2 = newer so thus key1=key2. This means that everytime I modify variable newer in a function call, it literally changes my previous key's values

For example in python I could do the following since everytime I call newer, it is a fresh variable that has no relationship with previous calls using newer.

def new(i,diction):
    newer = "hi" * i
    diction[newer] = "stuff" + str(i)


diction = {}
for i in range(10):
    new(i,diction)

print(diction)

Essentially result is {'': 'stuff0', 'hihi': 'stuff2', 'hihihihihihi': 'stuff6', 'hi': 'stuff1', 'hihihi': 'stuff3', 'hihihihi': 'stuff4', 'hihihihihihihi': 'stuff7 ', 'hihihihihihihihihi': 'stuff9', 'hihihihihihihihi': 'stuff8', 'hihihihihi': 'stuff5'}

I want to ask how to do the same thing in C

Answer 1

I want to reset the value of the char[] newer everytime my new function is called.

All you need is to initialise it properly:

char newer[45] = "";

As a general rule, you should always initialise local variable before using it. Failing to do so will usually lead to unexpected behaviour as you've seen in your code.