#include<stdio.h>#include<string>usingstd::string;
string size="hello!";
int main(){
size.append(1,'w');
cout<<size<<endl;//'cout' was not declared in this scopereturn0;
}
解决
#include<stdio.h>#include<iostream>//要素一#include<string>usingnamespacestd;//要素二string size="hello!";
int main(){
size.append(1,'w');
cout<<size<<endl;
return0;
}
示例二
#include<stdio.h>#include<iostream>#include<string>string size="hello!";
int main(){
size.append(1,'w');
cout<<size<<endl;
return0;
}
解决
#include<stdio.h>#include<iostream>#include<string>usingnamespacestd;//更准确的说法是*--using std::string--*string size="hello!";
int main(){
size.append(1,'w');
cout<<size<<endl;
return0;
}