String full summary

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Catalog

1. Commonly used STL Method

 Arbitrary base conversion ：
    itoa(int n,char* s,int r)  // take 10 Base number n Convert to r Base and assign to s
  Type conversion ：
         string ->int : string s("123");
                        int i = atoi(s.c_str());

         int -> string: int a;
                        stringstream(s) >> a;