string - Why did I get error by using strchr() in C++? -

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• c++ string equivalent strrchr 4 answers

#include <iostream> #include <string> #include <cstring> using namespace std;  int main(){     string a="asdasd";     if(!strchr(a,'a')) cout<<"yes";     return 0; }  

i began learn c++ programming , don't know why got error in line

if(!strchr(a,'a')) cout<<"yes"; 

but if tried code this, run well.

if(!strchr("asdasd",'a')) cout<<"yes"; 

i know stupid question don't know why.. sorry..

the library function strchr use c-style strings, not c++ string type.