set 的使用

set可以插入很多值，去掉重复元素，并可以查找

#include<iostream>#include<cstdio>#include<string>#include<set>using namespace std;int main(){    set<string> st;    st.clear(); //清空    string nm[]={"abc","david","lucy","abc","app","lucy"};    for(int i=0; i<6; i++)  st.insert(nm[i]); //st里插入元素     set<string>::iterator it; //set容器的指针     for(it=st.begin(); it!=st.end(); it++){        cout<<*it<<endl; //按字典序输出     } it=st.find("app");    if(it!=st.end()) cout<<"find"<<" "<<"app"<<endl;    else cout<<"can't find"<<" "<<"app"<<endl;    //找到了就输出find，找不到就输出can't find     it=st.find("bld");    if(it!=st.end()) cout<<"find"<<" "<<"bld"<<endl;    else cout<<"can't find"<<" "<<"bld"<<endl;    system("pause");}