random unwanted symbols in char array in C -

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im trying make array of strings using strcat(), keeps giving me unwanted characters, example: char arr[50] strcat(arr, "test") , when puts(arr) or printf("%s\n", arr), gives me @!*test instead of test, know what's causing problem?

thanks!

you must initialize array before using value, or invoke undefined behavior.

try this:

#include <stdio.h> #include <string.h>  int main(void) {     char arr[50] = {0}; /* add = {0} */     strcat(arr, "test");     puts(arr);     return 0; }

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