#include<stdio.h>
#define Fun(a,b) a##b
int main()
{
    x=‘H‘;
    y=‘W‘;
    printf("%s",Fun(x,y));
    return;
}

#include<stdio.h>
#define Var(x) var##x
int main()
{
    int Var(1)=1,Var(2)=2,Var(3)=3;
    printf("var1=%d\n",var1);
    printf("var2=%d\n",var2);
    printf("var3=%d\n",var3);
    return 0;
}