The following example shows one possibility. The user is asked to enter natural numbers (positive values 1, 2, 3, 4, etc). As each non-zero number is input, it is inserted into a global vector using an insertion sort algorithm which returns the index of the newly inserted value. The program then reports where the value was inserted before printing the vector. Entering the value 0 exits the program.

#include

using namespace std;

size_t insert(const int value, vector& v)

{

v.push_back( value );

size_t gap = v.size() - 1;

while( gap && value

{

v[gap]=v[gap-1];

--gap;

}

v[gap] = value;

return( gap );

}

int input_integer(string prompt)

{

int value = 0;

bool error = true;

while( error )

{

cout<

string response;

getline( cin, response );

stringstream ss(response);

if( ss>>value )

error = !error;

else

cout<<"Input error. Please try again.\n"<

}

return( value );

}

void print_vector(vector& v, string name)

{

cout<<"\nCurrent state of vector "<

for( size_t index=0; index

cout<

}

int main()

{

vector a;

while( int value = input_integer("Enter a natural number (0 to exit)"))

{

size_t index = insert( value, a );

cout<<"\nThe value "<

print_vector( a, "a" );

}

cout<

}

Output

Enter a natural number (0 to exit) 3

The value 3 was inserted at index 0

Current state of vector a:

a[0]=3

Enter a natural number (0 to exit) 2

The value 2 was inserted at index 0

Current state of vector a:

a[0]=2

a[1]=3

Enter a natural number (0 to exit) 1

The value 1 was inserted at index 0

Current state of vector a:

a[0]=1

a[1]=2

a[2]=3

Enter a natural number (0 to exit) 2

The value 2 was inserted at index 2

Current state of vector a:

a[0]=1

a[1]=2

a[2]=2

a[3]=3

Enter a natural number (0 to exit) 3

The value 3 was inserted at index 4

Current state of vector a:

a[0]=1

a[1]=2

a[2]=2

a[3]=3

a[4]=3

Enter a natural number (0 to exit) 0

Press any key to continue . . .

Resources

Top Categories

Product

Company