Test whether vector is empty
Returns whether the vector container is empty, i.e. whether its size is 0.
This function does not modify the content of the vector in any way. To clear the content of a vector, use vector::clear.
Parameters
none
Return Value
true if the vector size is 0, false otherwise.
Example
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
|
// vector::empty
#include <iostream>
#include <vector>
using namespace std;
int main ()
{
vector<int> myvector;
int sum (0);
for (int i=1;i<=10;i++) myvector.push_back(i);
while (!myvector.empty())
{
sum += myvector.back();
myvector.pop_back();
}
cout << "total: " << sum << endl;
return 0;
}
|
The example initializes the content of the vector to a sequence of numbers (form 1 to 10). It then pops the elements one by one until it is empty and calculates their sum.
Output:
Complexity
Constant.
See also
|