1.STL 概念
STL standard template libary 标准模(mu)板库 C++一部分，编译器自带
Android NDK支持
java.lang java.util包中API，java的一部分
string
1.1 string初始化
string s1 = "craig david";
string s2("7 days");
string s3 = s2;
string s4(10,'a');
1.2 常用方法
void main()
{
string s1 = "craig david";
// ^
//1 数组方式
for (int i = 0; i < s1.length(); i++)
{
cout << s1[i] << endl;
}
//2 迭代器指针
for (string::iterator it = s1.begin(); it != s1.end(); it++)
{
cout << *it << " ";
}
cout << endl;
//3 at函数(charAt)
// 可能会抛出异常
try
{
for (int i = 0; i < s1.length() + 3; i++)
{
cout << s1.at(i) << " ";
}
}
catch (...)
{
cout << "异常" << endl;
}
system("pause");
}
//string字符串->c字符串转换
void main()
{
//string -> char*
string s1 = "walking away";
const char* c = s1.c_str();
printf("%s\n",c);
//
string s2 = c;
//string->char[]
//从string中赋值字符到char[]
char arr[50] = {0};
s1.copy(arr,4,0);
cout << arr << endl;
system("pause");
}
//字符串拼接
void main()
{
string s1 = "alan";
string s2 = "jackson";
//1.
string s3 = s1 + s2;
string s4 = " pray";
//2.
s3.append(s4);
cout << s3 << endl;
system("pause");
}
//字符串查找替换
void main()
{
string s1 = "apple google apple iphone";
//从0开始查找"google"的位置
int idx = s1.find("google", 0);
cout << idx << endl;
//统计apple出现的次数
int idx_app = s1.find("apple",0);
//npos大于任何有效下标的值
int num = 0;
while (idx_app != string::npos)
{
num++;
cout << "找到的索引:" << idx_app << endl;
idx_app+=5;
idx_app = s1.find("apple", idx_app);
}
cout << num << endl;
system("pause");
}
//删除（截取）和插入
void main()
{
string s1 = "apple google apple iphone";
//删除a，找到a所在的指针
string::iterator it = find(s1.begin(),s1.end(),'g');
//只能删除一个字符
s1.erase(it);
//开头末尾插入字符串
s1.insert(0, "macos");
s1.insert(s1.length(), " facebook");
cout << s1 << endl;
system("pause");
}
//java StringBuffer才可变
//String 不可变
//大小写转换
void main()
{
string s1 = "JASON";
//原始字符串的起始地址，原始字符串的结束地址, 目标字符串的起始地址, 函数名称
transform(s1.begin(), s1.end()-1,s1.begin(), tolower);
cout << s1 << endl;
transform(s1.begin(), s1.end() - 1, s1.begin(), toupper);
cout << s1 << endl;
system("pause");
}
//容器
//Vector
//初始化
#include <vector>
void printVector(vector<int> &v)
{
//通过数组的方式遍历
for (int i = 0; i < v.size(); i++)
{
cout << v[i] << endl;
}
}
void main()
{
//1.
vector<int> v1;
v1.push_back(20);
v1.push_back(40);
v1.push_back(15);
v1.push_back(7);
//2.
vector<int> v2 = v1;
//3.部分复制
vector<int> v3(v1.begin(),v1.begin()+2);
printVector(v3);
system("pause");
}
//添加 删除
void main()
{
//添加到结尾
vector<int> v1;
v1.push_back(20);
v1.push_back(40);
v1.push_back(15);
v1.push_back(7);
//访问头部
v1.front() = 11;
//访问尾部
v1.back() = 90;
//删除结尾的元素
//v1.pop_back();
while (v1.size() > 0)
{
cout << "末尾的元素：" << v1.back() << endl;
v1.pop_back();
}
printVector(v1);
system("pause");
}
//数组的方式
void main()
{
vector<int> v1;
v1.push_back(20);
v1.push_back(40);
v1.push_back(15);
v1.push_back(7);
v1[2] = v1[2] +10;
//容器等价于动态数组
vector<int> v2(10);
for (int i = 0; i < v2.size(); i++)
{
v2[i] = i + 1;
}
printVector(v2);
system("pause");
}
//迭代器遍历
//迭代器的种类（正向，反向迭代器）
void main()
{
vector<int> v1;
v1.push_back(20);
v1.push_back(40);
v1.push_back(15);
v1.push_back(7);
//正向
for (vector<int>::iterator it = v1.begin(); it < v1.end(); it++)
{
cout << *it << endl;
}
cout << "-----------------" << endl;
//反向迭代
for (vector<int>::reverse_iterator it = v1.rbegin(); it < v1.rend(); it++)
{
cout << *it << endl;
}
system("pause");
}
//删除
void main()
{
vector<int> v1(10);
for (int i = 0; i < v1.size(); i++)
{
v1[i] = i + 1;
}
//删除指定位置
vector<int>::iterator it = v1.begin();
it += 3;
v1.erase(it);
//distance(v1.begin(), it);
//删除区间
v1.erase(v1.begin(), v1.begin() + 3);
for (vector<int>::iterator it = v1.begin(); it < v1.end(); it++)
{
if (*it == 5)
{
printf("%x\n", it);
vector<int>::iterator tmp = v1.erase(it); //注意以后开发中编译器版本问题
printf("%x,%x\n",it,tmp);
}
}
//插入
v1.insert(v1.begin() + 2, 100);
v1.insert(v1.end() - 1, 200);
printVector(v1);
system("pause");
}
//双向队列
#include <deque>
void printDeque(deque<int>& q)
{
for (int i = 0; i < q.size(); i++)
{
cout << q[i] << endl;
}
}
void main()
{
deque<int> d1;
//添加到尾部
d1.push_back(2);
d1.push_back(10);
//添加到头部
d1.push_front(-90);
d1.push_front(-30);
//printDeque(d1);
//cout << d1.front() << endl;
//cout << d1.back() << endl;
//两个方向弹出
//d1.pop_back();
//d1.pop_front();
printDeque(d1);
//查找第一个-90元素索引位置，无需遍历
deque<int>::iterator it = find(d1.begin(),d1.end(),-90);
if (it != d1.end())
{
int idx = distance(d1.begin(), it);
cout << "索引位置为：" << idx << endl;
}
system("pause");
}
