extern long double AL1Iteration(
   long double x,
   long double L,
   long double ( *f )( long double ),
   long double ( *f1 )( long double )
);
extern long double AL2Iteration(
   long double x,
   long double L,
   long double ( *f )( long double ),
   long double ( *f1 )( long double ),
   long double ( *f2 )( long double )
);
extern long double AL3Iteration(
   long double x,
   long double L,
   long double ( *f )( long double ),
   long double ( *f1 )( long double ),
   long double ( *f2 )( long double ),
   long double ( *f3 )( long double )
);
extern long double AL4Iteration(
   long double x,
   long double L,
   long double ( *f )( long double ),
   long double ( *f1 )( long double ),
   long double ( *f2 )( long double ),
   long double ( *f3 )( long double ),
   long double ( *f4 )( long double )
);

extern long double BL1Iteration(
   long double x,
   long double L,
   long double ( *f )( long double ),
   long double ( *f1 )( long double ),
   long double ( *f2 )( long double )
);
extern long double BL2Iteration(
   long double x,
   long double L,
   long double ( *f )( long double ),
   long double ( *f1 )( long double ),
   long double ( *f2 )( long double ),
   long double ( *f3 )( long double )
);
extern long double BL3Iteration(
   long double x,
   long double L,
   long double ( *f )( long double ),
   long double ( *f1 )( long double ),
   long double ( *f2 )( long double ),
   long double ( *f3 )( long double ),
   long double ( *f4 )( long double )
);
extern long double BL4Iteration(
   long double x,
   long double L,
   long double ( *f )( long double ),
   long double ( *f1 )( long double ),
   long double ( *f2 )( long double ),
   long double ( *f3 )( long double ),
   long double ( *f4 )( long double ),
   long double ( *f5 )( long double )
);