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  1.     #include <iostream>
  2.     #include <string.h>
  3.  
  4. 	int main() {
  5. 		for (size_t i = 0; i < 5; ++i) {
  6.             // foo1 and foo2 assignments clear the entire array.
  7. 			char foo1[1024] = "";
  8. 			char foo2[1024] = { 0 };
  9.             // this doesn't, so the previous values show thru in loop iterations.
  10. 			char foo3[1024];
  11. 			foo3[0] = '\0';
  12.  
  13. 			std::cout << i << ": foo1[9] = " << foo1[9] << ", foo2[9] = " << foo2[9] << ", foo3[9] = " << foo3[9] << std::endl;
  14.  
  15. 			strcpy(foo1, "123456789ABCDEF");
  16. 			strcpy(foo2, "123456789ABCDEF");
  17. 			strcpy(foo3, "123456789ABCDEF");
  18. 		}
  19.  
  20. 		return 0;
  21. 	}
Success #stdin #stdout 0s 3340KB
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stdin
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Standard input is empty
stdout
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0: foo1[9] = , foo2[9] = , foo3[9] = �
1: foo1[9] = , foo2[9] = , foo3[9] = A
2: foo1[9] = , foo2[9] = , foo3[9] = A
3: foo1[9] = , foo2[9] = , foo3[9] = A
4: foo1[9] = , foo2[9] = , foo3[9] = A
https://ideone.com/WmLtQp
Use of char array[] = ""
language:
C++14 (gcc 8.3)
created:
10 years ago
visibility:
public

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