再求助

不知道为什么两个结果不一样？？？？？？内层{}的意义是什么

#include<stdio.h>
#include<iostream.h>
#include<math.h>
main( )
{   
    char i,j,k;
    void show(char );
    for (i='X';i<='Z';i++)
        for (j='X';j<='Z'; j++)
            if (i!=j)
                for (k='X';k<='Z';k++)
                    if (i!=k&&j!=k)
                        if( i!='X'&&k!='X'&&k!='Z')
                        {printf("A--%c\tB--%c\tC--%c\n",i,j,k);
                        cout<<"A-";
                        show(i);
                        cout<<"B-";
                        show(j);
                        cout<<"C-";
                        show(k);}



        
}
void show(char p)   
{
if(p=='X')
cout<<"zhangsan\n";
if(p=='Y')
cout<<"lisi\n";
if(p=='Z')
cout<<"wangwu\n";
}


第二个#include<stdio.h>
#include<iostream.h>
#include<math.h>
main( )
{   
    char i,j,k;
    void show(char );
    for (i='X';i<='Z';i++)
        for (j='X';j<='Z'; j++)
            if (i!=j)
                for (k='X';k<='Z';k++)
                    if (i!=k&&j!=k)
                        if( i!='X'&&k!='X'&&k!='Z')
                        printf("A--%c\tB--%c\tC--%c\n",i,j,k);
                        cout<<"A-";
                        show(i);
                        cout<<"B-";
                        show(j);
                        cout<<"C-";
                        show(k);



        
}
void show(char p)   
{
if(p=='X')
cout<<"zhangsan\n";
if(p=='Y')
cout<<"lisi\n";
if(p=='Z')
cout<<"wangwu\n";
}