Adjust VBA macro for a fixed location and remove user input

The macro below does perform the task I need correctly. It takes the values from column A&B and insert them into column C. The Input Box entries are A:B on the first and C1 on the second one. I would like to remove the input boxes and have the macro run without user input. The sheet will always be Date_Validation using columns A:B with an input into C. The macro below uses C1 as the input cell where in column C both A&B columns are joined with only unique values remaining. The macro does appear to calculate for a header since you select C1 but the data starts in C2. Can this be cleaned up to just run without input. I don't understand the code below, any help would be great so I can learn
Thanks

Sub FindUniques()
'Updateby20140313
Sheets("Date_Validation").Select
'Added Range to test
Range("A:B").Select
Dim rng As Range
Dim InputRng As Range, OutRng As Range
xTitleId = "KutoolsforExcel"
Set InputRng = Application.Selection
Set InputRng = Application.InputBox("Range A:B :", xTitleId, InputRng.Address, Type:=8)
Set OutRng = Application.InputBox("Output to ( C1 ):", xTitleId, Type:=8)
Set dic = CreateObject("Scripting.Dictionary")
For j = 1 To InputRng.Columns.Count
For i = 1 To InputRng.Rows.Count
xValue = InputRng.Cells(i, j).Value
If xValue <> "" And Not dic.Exists(xValue) Then
OutRng.Value = xValue
dic(xValue) = ""
Set OutRng = OutRng.Offset(1, 0)
End If
Next
Next
End Sub

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The macro can be edited to use without the input boxes ... however, you need to be more specific.

What rows in Col A & B are you targeting and will the data always be pasted to C1 ?

The attached macro did not require a row length. I have formulas down to row 7500 for both columns. Data in A&B will vary daily. Currently down to row 7500 is covering the largeest data set entered. A range of A2 thru B7500 would handle it if you need a range. The attached macro required a selection of C1 to ccopy the data from column A & B, remove the duplicates and paste starting cell C2. The above macro accounted for a header. The C column and cell C2 will always be where the combined data will go

I tried your macro suggestion and it appeared slow and column C had blanks mixed in with the data pasted. The original macro does work perfectly, but requires user input. Is there any way to adjust that one. Input will always be from A:B and output to C1 based on this macro code which has an offset to actually enter the data in C2 when final pasting. I adjusted the message box statement to state using A:B and C1. I didnt understand the code to have these preselected Thanks

Hello, I ran this macro today with the changes. It does run quickly. There are headers in all columns including A,B,C. I changed the Range("c1") to c2 which did correct that issue. The only problem I am still having is the the final data, the combined values from A& B into C after removing duplicates(Only Unique Values) is adding one blank cell in the middle of the data in Column C. Is there a way to not have this occur? Thanks

Hello, I ran the new data set again today and still get the same error where a blank cell is mixed into Column C. I checked the cell for content and couldn't find any. Would you know why this occurs and how this can be avoided. The data is new each day in columns A:B. Would a sort function prior to pasting just add the blank to the end?

Hi, I tried this version. The macro fails in the lines below

With Sheets("Date_Validation")
.Range("C2", .Range("C" & .Rows.Count).End(xlUp)).ClearContents
.Range("C2").Resize(.Count) = Application.Transpose(Dic.keys)
End With

The 1st line starting with .Range("C2") is clearing out the header and the second .range line is bugging. The macro stops and highlights the 2nd line.

Thank You Its not as fast but worked fine