main()
 {
   print(  mysub( 6 ) );
 }

Example Program: Factorial( N )

The next example program prompts the user for an integer, reads in the integer, and prints the factorial. The SPIM console window is at right. The pseudo-code for the program is:

#  main()
#  {
#    int a, b;  // a: 0($fp),  b: 4($fp)
#    write("enter an int:")
#    read( a );
#    b = fact( a );
#    write("factorial is:")
#    print( b );
#  }

#  int fact( int n )
#  {
#    if ( n <= 1 )
#      return 1;
#    else
#      return n*fact(n-1);
#  }