c++字符类型

#include "iostream"

using namespace std;
int main(){
    int a=88+3;
    cout<<"a="<<a<<" "<<char(a)<<endl;
    cout<<"sizoef a "<<sizeof(a)<< endl;
    if ('3'<51)cout<<"ok1\n";
    if ('3'==51)cout<<"ok2\n";
    if ('3'>51)cout<<"ok3\n";
}

a=91 [
sizoef a 4
ok2