# 给vector去重复的三个方法

## 方法一、利用set容器

```c++
#include <iostream>
#include <vector>
#include <set>

using namespace std;

int main(){
    int myInts[] = {1, 2, 3, 1, 1};
    int len = sizeof(myInts)/sizeof(int);
    
    vector<int> vec(myInts, myInts+len);
    set<int> s(vec.begin(), vec.end());
    //我觉得最好新建一个vector对象
    vec.assign(s.begin(), s.end());
    
    for(int x: vec){
        cout << x << ", ";
    }
    return 0;
}
```

## 方法二、结合sort和unique函数

```c++
#include <iostream>
#include <algorithm>
#include <vector>

using namespace std;

int main(){
    int myints[] = {1,2,3,1,1};
    int len = sizeof(myints)/sizeof(int);
    vector<int> vec(myints, myints + len);
    sort(vec.begin(), vec.end());
    //这样不行,最好的解决方案还是方法一
    //vec.erase(unique(vec.begin(), vec.end()));
    vec.erase(unique(vec.begin(), vec.end()), vec.end());
    
    for(int x: vec){
        cout << x << ", ";
    }
    return 0;
}
```

## 方法三、使用remove函数

```c++
#include <iostream>
#include <vector>
#include <algorithm>
#include <functional>

using namespace std;

int main(){
    std::vector<int> vec(0);
    for(int i = 0 ; i < 10; i++)
    {
        vec.push_back(i);  
    }
    vec.push_back(7);
    auto ret = std::remove(vec.begin(), vec.end(), 7);
    vec.erase(ret, vec.end());

    for(auto &i : vec)
    {
        std::cout << i << " " << std::endl;
    }
    return 0;
}
```


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