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Array and Vector

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# 1  
Old 11-10-2011
Array and Vector
Hi all, from my understanding I understand that I can use array in this manner.

Code:
struct test
{
   int a;
   int b;
   int c;
};
 
test testing[10]; //creating an array with the structer type
 
testing[1].a=1;
testing[2].b=2;
testing[3].c=3;

If I'm not wrong we can use array in this manner, however is it possible to do the same using "vector"?
# 2  
Old 11-10-2011
Yes, you can use both arrays and vectors in this manner. A vector acts just like an array with extras.

Be careful never to access elements that don't exist, remembering that arrays in C and C++ count from zero:

Code:
int n[4];

n[3]=5; // Last valid element
n[4]=5; // THIS MAY CRASH OR DO WEIRD THINGS

vector<int> v;
v.resize(4);
v[3]=5; // Last valid element
v[4]=5; // THIS MAY CRASH OR DO WEIRD THINGS

# 3  
Old 11-10-2011
Thanks corona! For the codes below, if I want to use vector instead of array. How should I do it to achieve the same result?

Code:
struct test
{
   int a;
   int b;
   int c;
};
 
test testing[10]; //creating an array with the structer type
 
testing[1].a=1;
testing[2].b=2;
testing[3].c=3;

# 4  
Old 11-11-2011
to make a vector of int, do vector<int>
to make a vector of test, do vector<test>
to make a vector of slartibartfast, do vector<slartibartfast>
# 5  
Old 11-12-2011
Quote:
Originally Posted by vinzping
...if I want to use vector instead of array. How should I do it to achieve the same result?

Code:
struct test
{
   int a;
   int b;
   int c;
};
 
test testing[10]; //creating an array with the structer type
 
testing[1].a=1;
testing[2].b=2;
testing[3].c=3;

To create vector change the type from array to array of pointers to struct test or an "Iliffe Vector"...
Code:
struct test *testing[10];

# 6  
Old 11-12-2011
Quote:
Originally Posted by shamrock
To create vector change the type from array to array of pointers to struct test or an "Iliffe Vector"...
Code:
struct test *testing[10];

Which helps how exactly? it can't be used as an ordinary array anymore, and each element must be allocated individually...
# 7  
Old 11-14-2011
Quote:
Originally Posted by Corona688
Which helps how exactly? it can't be used as an ordinary array anymore, and each element must be allocated individually...
That is left as an exercise for the op...i provided an example of a vector not its implementation.
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