Wrong Answer on submit

my code is working fine for sample test case but on submit it is showing run time error and wrong answer my code:- https://repl.it/@mohdimran001/merge-sort#main.cpp

at line 65 use : ll arr[200000];
ll arr[n] is wrong as on compilation time value of n is no known compiler give a random size to arr
after using this all testcase will pass

Modified Code

i hope this help
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