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  1. #include <iostream>
  2. #include <stdio.h>
  3. #include <stdlib.h>
  4. #include <string.h>
  5.  
  6. namespace X{
  7. 	void out(const char *str1, const char *str2, char *str3, int m, int n, int index)
  8. 	{
  9. 		if (!m && !n)
  10. 			std::cout<<str3<<std::endl;
  11.  
  12. 		if (m) {
  13. 			str3[index] = str1[0];
  14. 			out(str1+1, str2, str3, m-1, n,index+1);
  15. 		}
  16. 		if (n) {
  17. 			str3[index] = str2[0];
  18. 			out(str1,str2+1, str3, m, n-1, index+1);
  19. 		}
  20. 	}
  21.  
  22. 	bool isstringsum (const char *str1, const char *str2, const char *str3) {
  23. 		while (*str3) {
  24. 			if(*str1==*str3) ++str1;
  25. 			else if(*str2==*str3) ++str2;
  26. 			else return false;
  27. 			++str3;
  28. 		}
  29.  
  30. 		if(*str1||*str2)
  31. 			return false;
  32. 		return true;
  33. 	}
  34. }
  35.  
  36. int main()
  37. {
  38. 	char *str1 = "ab";
  39. 	char *str2 = "c";
  40.  
  41. 	int m = strlen(str1);
  42. 	int n = strlen(str2);
  43.  
  44. 	char *strout= (char*) malloc((m+n+1)*sizeof(char));
  45. 	strout[m+n] = '\0';
  46.  
  47. 	std::cout<<"result:"<<std::endl;
  48. 	X::out (str1, str2, strout, m,n, 0);
  49.  
  50. 	char *str3 = "cab";
  51. 	X::isstringsum(str1,str2,str3)?std::cout<<"ok"<<std::endl:std::cout<<"error"<<std::endl;
  52.  
  53. 	free(strout);
  54.     return 0;
  55. }
Success #stdin #stdout 0.01s 2856KB
comments (?)
stdin 
Standard input is empty
stdout 
result:
abc
acb
cab
ok
https://ideone.com/o1klw
language:
C++ (gcc 8.3)
created:
13 years ago
visibility:
public

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