string

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#include <iostream>
#include <string>

using namespace std;

int main(void){
    string arr = "hello world";
    string s(5,'a');
    string s1("three")
    
    cout << arr <<endl;
    cout << s <<endl;
    cout << s1 <<endl;
    
}
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string a = "hello";
a = "pre" + a + "world";

cout << a <<endl;
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string str;
getline(cin,str);
cout << str.empty() <<endl;
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str.replace(2,3,"ABCD",2,2);
str.erase(3,1);

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str.c_str();
#turn string into a const string
char* p = (char*)str.c_str();


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istringstream is(src);

string s1;
int a;
double b;
char c;

is >> s1 >> a >> b >> c;


ostringstream os;
os << s1 <<" "<< a << " " << b << " " <<c;

foreach &

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int arr[] = {1,2,3,4,5};

for(int x:arr){
	cout<<x<<endl;
}


int a = 2;
int& b = a;
b = 4;
cout<<a<<endl;

for(int &x:arr){
	x = 1;
}
for(int x:arr){
	cout<<x<<endl;
}


static

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void f(){
	static int num = 0;
	num++;
	cout << num << endl;
}
int main(){
	
	f();
	f();

}

默认参数

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模板化，泛型

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#include <iostream>
using namespace std;

template<class T>
bool maxA(T a,T b){
	return a > b;
}

int main() {
	
	cout << maxA(10,20) << endl;
	cout << maxA('a','b') << endl;
	cout << maxA<int>(20.6,10) << endl;
}

vector

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