program exp3 (input,output); {9%}
CONST N=10;
VAR S,I : INTEGER;
FUNCTION CO(I1:INTEGER) : INTEGER;
VAR J1,S1 : INTEGER;
BEGIN
S1:=N;
FOR J1:= (N-1) DOWNTO (N-I1+1) DO
S1:= S1*J1 DIV (N-J1+1);
CO:=S1
END;
BEGIN
S:=N+1;
FOR I:= 2 TO N DO S:=S + CO(I);
WRITELN(‘S=’,S);
END.
输出：S=1024