%plot% demo

@echo off & setlocal enableDelayedExpansion

mode 53,53

set ^"LF=^

^" Above empty line is required - do not remove
set ^"\n=^^^%LF%%LF%^%LF%%LF%^^"

set plot=for %%# in (1 2) do if %%#==2 ( for /f "tokens=1-3" %%1 in ("^!args^!") do (%\n%
    set /a "_y=%%2", "_x=%%1", "_x2=%%1 + 1"%\n%
    for /f "tokens=1-4" %%a in ("_y ^!_y^! ^!_x^! ^!_x2^!") do set "_[^!%%a^!]=^!_[%%b]:~0,%%c^!%%3^!_[%%b]:~%%d^!"%\n%
)) else set args=




for /l %%a in (1,1,50) do set "_[%%a]=                                                  "

for /l %%a in (1,1,50) do (
    set /a "r1=!random! %% 49 + 1
    set /a "r2=!random! %% 49 + 1

    %plot% r1 r2 @
)

echo ####################################################
for /l %%a in (1,1,50) do echo=#!_[%%a]!#
echo ####################################################
pause & exit