force correct input

[learningcplusplus898]

in my county registration number, consists of 6 charaters( numbers/letters )

trying to force correct input so will allways exit function with total of 6 characters in the string.
problem happens when it gets to while loop.

# include <iostream>
# include <conio.h>
using namespace std;

int main()
{
	char rego[8];
	int j = 0;
	int c = 0;
	cout << "enter rego number ";

	cin >> rego;

	cout << "you said " << rego << endl;

	int i = 0;
	for( i ; i < strlen( rego ); i++ )
	{
	    //cout << i; getch();
	     c++;
	}
	cout << i; getch();
	int k = 0;
	if( i != 6 )
	{
	  cout << c <<"ERROR:";

	 while( i != 6 || k == 6 ) )
	 {
	  cout << "enter 6 character rego ";
	  cin >> rego;  

		for( j ; j < strlen( rego ); j++ )
		{
	          for( k; k < j; k++ )
		  {
	            //cout << rego[k];getch();
		  }
	         }
		//cout << j;
	  cout << k;getch();
	  }

	}

 cout << "passed";getch();

}

[cire]

If i is not equal to 6, then i will never be 6 on line 28. Instant infinite loop.

In addition, you never reset the values of j or k, although you clearly should.

#include <iostream>
#include <string>

int main()
{
    std::string line;
    std::cout << "Enter a 6 character rego:\n> ";

    while (getline(std::cin, line) && line.length() != 6)
        std::cout << "ERROR: You must enter a 6 character rego.\n> ";

    std::cout << "You entered \"" << line << "\"\n";
}

[learningcplusplus898]

great thanks, i see where i went wrong now.

reset values? why should i do that?

#include <iostream>
#include <string>
#include <string.h>
using namespace std;

int main()
{
	char rego[ 8 ];

	cout << "enter rego number ";
	cin >> rego;

	while( strlen( rego ) != 6 )
	{
		cout << "ERROR: enter 6 character rego ";
		cin >> rego;
	}

}

[cire]

reset values? why should i do that?

Because the program logic required it.

Your code is error prone. Consider using a std::string or otherwise limiting the input extracted into rego to what the buffer can actually hold.