PROCEDURE STRMTCH (N,M: INTEGER;VAR  KEY:INTEGER; S,P:SS);
   VAR  I,J,K:INTEGER;
BEGIN
    I:=0;
 KEY:=0;
    WHILE I < N DO BEGIN
      I:=I+1; J:=I; K:=1;
     WHILE (S[ J ]=P[ K ]) AND (KEY=0) DO
      IF K=M THEN KEY:=1
             ELSE BEGIN
               J:=J+1 ; K:=K+1 ;
         END
    END
END ;