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 For

loop command
 Syntax
 ``` For I := N_1 To N_2 Do C EndFor For I := N_1 To N_2 Step D Do C EndFor where I is a dummy variable, N_1, N_2, and D are integer expressions, and C is a sequence of commands. ```

 Description
In the first form, the variable I is assigned the values N_1, N_1+1, ...,N_2 in succession. After each assignment, the command sequence C is executed. The second form is the same, except that I is assigned the values N_1, N_1+D, N_1+2D, etc. until the greatest value less than or equal to N_2 is reached. If N_2 < N_1, then C is not executed.

Note: Large values for N_1, N_2, or D are not permitted; typically they should lie in the range about -10^9 to +10^9.

Note: Don't forget the capitalization in the word To.

 Example
 ``` For N := 1 To 5 Do Print 2^N, " "; EndFor; 2 4 8 16 32 ------------------------------- For N := 1 To 20 Step 3 Do Print N, " "; EndFor; 1 4 7 10 13 16 19 ------------------------------- For N := 10 To 1 Step -2 Do Print N, " "; EndFor; 10 8 6 4 2 ------------------------------- For N := 5 To 3 Do Print N, " "; EndFor; -- no output ```
Loops can be nested.

 Example
 ``` Define Sort(Var(L)) For I := 1 To Len(L)-1 Do M := I; For J := I+1 To Len(L) Do If L[J] < L[M] Then M := J EndIf; EndFor; If M <> I Then C := L[M]; L[M] := L[I]; L[I] := C EndIf; EndFor; EndDefine; M := [5,3,1,4,2]; Sort(M); M; [1, 2, 3, 4, 5] ------------------------------- ```
(Note that Var(L) is used so that the function can change the value of the variable referenced by L. See Var.)