unordered_multimap::clear()是C++ STL中的內置函數,可清除unordered_multimap容器中的內容。調用該函數後,容器的最終大小為0。
用法:
unordered_multimap_name.clear()
參數:該函數不接受任何參數。
返回值:它什麽也不返回。
以下示例程序旨在說明上述函數:
示例1:
// C++ program to illustrate the
// unordered_multimap::clear()
#include <bits/stdc++.h>
using namespace std;
int main()
{
// declaration
unordered_multimap<int, int> sample;
// inserts key an delement
sample.insert({ 10, 100 });
sample.insert({ 10, 100 });
sample.insert({ 20, 200 });
sample.insert({ 30, 300 });
sample.insert({ 15, 150 });
cout << "Key and Elements of multimap are:";
for (auto it = sample.begin(); it != sample.end(); it++) {
cout << "\n{" << it->first << ", " << it->second << "}";
}
sample.clear();
cout << "\nSize of container after function call: "
<< sample.size();
return 0;
}
輸出:
Key and Elements of multimap are: {15, 150} {30, 300} {20, 200} {10, 100} {10, 100} Size of container after function call: 0
示例2:
// C++ program to illustrate the
// unordered_multimap::clear()
#include <bits/stdc++.h>
using namespace std;
int main()
{
// declaration
unordered_multimap<char, char> sample;
// inserts element
sample.insert({ 'a', 'b' });
sample.insert({ 'a', 'b' });
sample.insert({ 'b', 'c' });
sample.insert({ 'r', 'a' });
sample.insert({ 'c', 'b' });
cout << "Key and Elements of multimap are:";
for (auto it = sample.begin(); it != sample.end(); it++) {
cout << "\n{" << it->first << ", " << it->second << "}";
}
sample.clear();
cout << "\nSize of container after function call: "
<< sample.size();
return 0;
}
輸出:
Key and Elements of multimap are: {c, b} {r, a} {b, c} {a, b} {a, b} Size of container after function call: 0
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注:本文由純淨天空篩選整理自gopaldave大神的英文原創作品 unordered_multimap clear() function in C++ STL。非經特殊聲明,原始代碼版權歸原作者所有,本譯文未經允許或授權,請勿轉載或複製。