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<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html><head> <meta name="generator" content= "HTML Tidy for Linux/x86 (vers 1 September 2005), see www.w3.org"> <title>end</title> <link href="../cppreference.css" rel="stylesheet" type="text/css"></head><body><table> <tr> <td> <div class="body-content"> <div class="header-box"> <a href="../index.html">cppreference.com</a> > <a href= "index.html">C++ Vectors</a> > <a href="end.html">end</a> </div> <div class="name-format"> end </div> <div class="syntax-name-format"> Syntax: </div> <pre class="syntax-box"> #include <vector> iterator end(); const_iterator end() const;</pre> <p>The end() function returns an iterator just past the end of the vector.</p> <p>Note that before you can access the last element of the vector using an iterator that you get from a call to end(), you'll have to decrement the iterator first. This is because end() doesn't point to the end of the vector; it points <strong>just past the end of the vector</strong>.</p> <p>For example, in the following code, the first "cout" statement will display garbage, whereas the second statement will actually display the last element of the vector:</p> <pre class="example-code"> vector<int> v1; v1.push_back( 0 ); v1.push_back( 1 ); v1.push_back( 2 ); v1.push_back( 3 ); int bad_val = *(v1.end()); cout << "bad_val is " << bad_val << endl; int good_val = *(v1.end() - 1); cout << "good_val is " << good_val << endl;</pre> <p>The next example shows how <a href= "begin.html">begin</a>() and end() can be used to iterate through all of the members of a vector:</p> <pre class="example-code"> vector<int> v1( 5, 789 ); vector<int>::iterator it; for( it = v1.begin(); it != v1.end(); it++ ) { cout << *it << endl; } </pre> <p>The iterator is initialized with a call to <a href= "begin.html">begin</a>(). After the body of the loop has been executed, the iterator is incremented and tested to see if it is equal to the result of calling end(). Since end() returns an iterator pointing to an element just after the last element of the vector, the loop will only stop once all of the elements of the vector have been displayed.</p> <p>end() runs in <a href="../complexity.html">constant time</a>.</p> <div class="related-name-format"> Related topics: </div> <div class="related-content"> <a href="begin.html">begin</a><br> <a href="rbegin.html">rbegin</a><br> <a href="rend.html">rend</a> </div> </div> </td> </tr> </table></body></html>⌨️ 快捷键说明
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