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how to calculate no of elements in an array

prajesh (8)
for example
char *a[]={"abc","def","ghi"};
pls help me!
MiiNiPaa (8886)
YOu can do this only if array was not passed into any function, because arrays degenerate to pointers when you do that.

Safe C++ way to do it:
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#include <iostream>

template <typename T, size_t N>
size_t array_size(T (&)[N])
{
    return N;   
}

int main()
{
    //Usage
    const char *a[]={"abc","def","ghi"};
    std::cout << array_size(a);
}
 
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http://coliru.stacked-crooked.com/a/61a4f0d7be5271ea
prajesh (8)
thanks a lot i got this in another way


char *c={"abc",def"};
return sizeof(c)/sizeof(c[0]);


output:
2

MiiNiPaa (8886)
thanks a lot i got this in another way
Note that this way requires constant programmer attention as it does not prevent array from decaying to pointer: http://coliru.stacked-crooked.com/a/a758ffb73dd09b1c
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#include <iostream>

size_t array_size(const char* c[])
{
    return sizeof(c)/sizeof(c[0]);  
}

int main()
{
    //Usage
    const char *a[]={"abc","def","ghi"};
    std::cout << array_size(a);
}
 
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Ericool (522)
you can also use std::array template.
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