let(@),n=String.make,read_int()/3open Printf;;for i=1to n do printf"%*s%*s "(n-i+2)"/"(i*2-1)"\\"done;printf"/%s\\ "(n*2@'_');for i=1to n do printf"|%*s%*s%*s "i"\\"(n*2-i*2+1)"/"i"|"done;for i=0to n-2do printf"|%*s%*s%*s "(n-i)"/"(i*2+1)"\\"(n-i)"|"done;printf"|/%s\\|"(n*2-2@'_')
Note that non-ascii characters in the above source code will be escaped (such as \x9f).