Unable to initialize char [] var inside struct ....

can't compile no combination I write.....

Code:

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struct my_struct {
 int var1;
 char txt[50];
 my_struct(){
 var1=0; 
 txt = ??????????  
 };
};

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I'd want to initialize txt to zero characters (empty), or 50 blank spaces.
I need help ......
Thanks

Code:

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#define TXT_SIZE 50
 
struct my_struct {
 int var1;
 char txt[TXT_SIZE];
 my_struct(){
 var1=0; 
 memset(txt,0,sizeof(char)*TXT_SIZE);
 }
};

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