Initial data commit

Task/String-matching/Fortran/string-matching-1.f

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+      SUBROUTINE STARTS(A,B)	!Text A starts with text B?
+       CHARACTER*(*) A,B
+        IF (INDEX(A,B).EQ.1) THEN	!Searches A to find B.
+          WRITE (6,*) ">",A,"< starts with >",B,"<"
+         ELSE
+          WRITE (6,*) ">",A,"< does not start with >",B,"<"
+        END IF
+      END SUBROUTINE STARTS
+
+      SUBROUTINE HAS(A,B)	!Text B appears somewhere in text A?
+       CHARACTER*(*) A,B
+       INTEGER L
+        L = INDEX(A,B)		!The first position in A where B matches.
+        IF (L.LE.0) THEN
+          WRITE (6,*) ">",A,"< does not contain >",B,"<"
+         ELSE
+          WRITE (6,*) ">",A,"< contains a >",B,"<, offset",L
+        END IF
+      END SUBROUTINE HAS
+
+      SUBROUTINE ENDS(A,B)	!Text A ends with text B.
+       CHARACTER*(*) A,B
+       INTEGER L
+        L = LEN(A) - LEN(B)	!Find the tail end of A that B might match.
+        IF (L.LT.0) THEN	!Dare not use an OR, because of full evaluation risks.
+          WRITE (6,*) ">",A,"< is too short to end with >",B,"<"	!Might as well have a special message.
+        ELSE IF (A(L + 1:L + LEN(B)).NE.B) THEN	!Otherwise, it is safe to look.
+          WRITE (6,*) ">",A,"< does not end with >",B,"<"
+        ELSE
+          WRITE (6,*) ">",A,"< ends with >",B,"<"
+        END IF
+      END SUBROUTINE ENDS
+
+      CALL STARTS("This","is")
+      CALL STARTS("Theory","The")
+      CALL HAS("Bananas","an")
+      CALL ENDS("Banana","an")
+      CALL ENDS("Banana","na")
+      CALL ENDS("Brief","Much longer")
+      END