Language
C++
Compiler
gcc HEAD 12.0.0 20210721 (experimental)
Options
Warnings
Boost 1.73.0
C++2b(GNU)
no pedantic
$ g++ prog.cc -Wall -Wextra -I/opt/wandbox/boost-1.73.0/gcc-head/include -std=gnu++2b list: 1 2 3 4 5
list: 1 3 4 5
list: 1 3 5
list: 1 3 9 5
n1: prev = 0, next = 3
n3: prev = 1, next = 9
n9: prev = 3, next = 5
n5: prev = 9, next = 0
Exit Code:
0