PROGRAM TESTADD; VAR A,B,C,D,E,F,G,H:INTEGER; PROCEDURE BLAH(Q,R:INTEGER; VAR S:INTEGER); EXTERNAL; BEGIN READ(A); READ(B); BLAH(A,B,C); WRITE(C);WRITELN; READ(E); BLAH(E,C,F); WRITE(E);WRITELN; READ(G); BLAH(G,F,H); WRITE(H);WRITELN; END.