在STL中实现Vector的C ++程序
向量具有在插入或删除元素时自动像动态数组一样自动调整大小的能力，容器可以自动处理其存储。矢量元素放置在连续的存储中，以便可以使用迭代器对其进行访问和遍历。可以在向量的开头，中间或结尾插入或删除数据。
功能和说明：
List of functions used here: v.size() = Returns the size of vector. v.push_back() = It is used to insert elements to the vector from end. v.pop_back() = To pop out the value from the vector from back. v.capacity() = Returns the size of the storage space currently allocated to the vector as number of elements. v.clear() = Clears the vector.
范例程式码
#include <iostream>
#include <vector>
using namespace std;
int main() {
vector<int> v;
vector<int>::iterator it;
int c, i;
while (1) {
cout<<"1.Size of the Vector"<<endl;
cout<<"2.Insert Element into the Vector"<<endl;
cout<<"3.Delete Last Element of the Vector"<<endl;
cout<<"4.Display the capacity of vector"<<endl;
cout<<"5.Display by Iterator"<<endl;
cout<<"6.Clear the Vector"<<endl;
cout<<"7.Exit"<<endl;
cout<<"Enter your Choice: ";
cin>>c;
switch(c) {
case 1:
cout<<"Size of Vector: ";
cout<<v.size()<<endl;
break;
case 2:
cout<<"Enter value to be inserted: ";
cin>>i;
v.push_back(i);
break;
case 3:
cout<<"Delete Last Element Inserted:"<<endl;
v.pop_back();
break;
case 4:
cout<<"Displaying capacity of vector: ";
cout<<v.capacity()<<endl;
break;
case 5:
cout<<"Displaying Vector by Iterator: ";
for (it = v.begin(); it != v.end(); it++) {
cout<<*it<<" ";
}
cout<<endl;
break;
case 6:
v.clear();
cout<<"Vector Cleared"<<endl;
break;
case 7:
exit(1);
break;
default:
cout<<"Wrong Choice"<<endl;
}
}
return 0;
}输出结果
1.Size of the Vector 2.Insert Element into the Vector 3.Delete Last Element of the Vector 4.Display the capacity of vector 5.Display by Iterator 6.Clear the Vector 7.Exit Enter your Choice: 1 Size of Vector: 0 1.Size of the Vector 2.Insert Element into the Vector 3.Delete Last Element of the Vector 4.Display the capacity of vector 5.Display by Iterator 6.Clear the Vector 7.Exit Enter your Choice: 2 Enter value to be inserted: 7 1.Size of the Vector 2.Insert Element into the Vector 3.Delete Last Element of the Vector 4.Display the capacity of vector 5.Display by Iterator 6.Clear the Vector 7.Exit Enter your Choice: 2 Enter value to be inserted: 6 1.Size of the Vector 2.Insert Element into the Vector 3.Delete Last Element of the Vector 4.Display the capacity of vector 5.Display by Iterator 6.Clear the Vector 7.Exit Enter your Choice: 2 Enter value to be inserted: 4 1.Size of the Vector 2.Insert Element into the Vector 3.Delete Last Element of the Vector 4.Display the capacity of vector 5.Display by Iterator 6.Clear the Vector 7.Exit Enter your Choice: 2 Enter value to be inserted: 3 1.Size of the Vector 2.Insert Element into the Vector 3.Delete Last Element of the Vector 4.Display the capacity of vector 5.Display by Iterator 6.Clear the Vector 7.Exit Enter your Choice: 2 Enter value to be inserted: 5 1.Size of the Vector 2.Insert Element into the Vector 3.Delete Last Element of the Vector 4.Display the capacity of vector 5.Display by Iterator 6.Clear the Vector 7.Exit Enter your Choice: 4 Displaying capacity of vector: 8 1.Size of the Vector 2.Insert Element into the Vector 3.Delete Last Element of the Vector 4.Display the capacity of vector 5.Display by Iterator 6.Clear the Vector 7.Exit Enter your Choice: 5 Displaying Vector by Iterator: 7 6 4 3 5 1.Size of the Vector 2.Insert Element into the Vector 3.Delete Last Element of the Vector 4.Display the capacity of vector 5.Display by Iterator 6.Clear the Vector 7.Exit Enter your Choice: 3 Delete Last Element Inserted: 1.Size of the Vector 2.Insert Element into the Vector 3.Delete Last Element of the Vector 4.Display the capacity of vector 5.Display by Iterator 6.Clear the Vector 7.Exit Enter your Choice: 5 Displaying Vector by Iterator: 7 6 4 3 1.Size of the Vector 2.Insert Element into the Vector 3.Delete Last Element of the Vector 4.Display the capacity of vector 5.Display by Iterator 6.Clear the Vector 7.Exit Enter your Choice: 6 Vector Cleared 1.Size of the Vector 2.Insert Element into the Vector 3.Delete Last Element of the Vector 4.Display the capacity of vector 5.Display by Iterator 6.Clear the Vector 7.Exit Enter your Choice: 7 Exit.