c++ - Inputting into a char* declared earlier crashes the program while doing that into a 'just-declared' char* doesn't. Why? -

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this code crashes program

#include <cstdio> int main() {     char *name1;     char *name2 = "mark";     gets(name1);     puts(name1);     return 0; }

whereas doesn't

#include <cstdio> int main() {     char *name1 = "mark";     char *name2;     gets(name2);     puts(name2);     return 0; }

why ? using mingw code::blocks ide.

you lucky 1 crashes , other doesn't.
both of programs produce undefined behavior.

char *name2; gets(name2);

you need point pointer valid , big enough memory able write it. writing uninitialized pointer. results in undefined behavior. undefined behavior not mandate crash, literally means behavior possible, in case might crash , may not nevertheless incorrect program.

ideal solution use std::string.
if insist on using char * need point pointer valid memory. e.g.

char myarr[256]; char *name2 = &myarr;

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