Removed odd memory access

Author: artemgl

src/GraphBLAS-sharp/Implementations.fs

@@ -240,12 +240,12 @@ and COOMatrix<'a when 'a : struct and 'a : equality>(rowCount: int, columnCount:
                         let secondColumn = secondColumnsBuffer.[boundaryY]
 
                         if boundaryX < 0 || boundaryY >= 0 && (firstRow < secondRow || firstRow = secondRow && firstColumn < secondColumn) then
-                            allRowsBuffer.[i] <- secondRowsBuffer.[boundaryY]
-                            allColumnsBuffer.[i] <- secondColumnsBuffer.[boundaryY]
+                            allRowsBuffer.[i] <- secondRow
+                            allColumnsBuffer.[i] <- secondColumn
                             allValuesBuffer.[i] <- secondValuesBuffer.[boundaryY]
                         else
-                            allRowsBuffer.[i] <- firstRowsBuffer.[boundaryX]
-                            allColumnsBuffer.[i] <- firstColumnsBuffer.[boundaryX]
+                            allRowsBuffer.[i] <- firstRow
+                            allColumnsBuffer.[i] <- firstColumn
                             allValuesBuffer.[i] <- firstValuesBuffer.[boundaryX]
             @>