answer.code:37:12: warning: use of ‘auto’ in parameter declaration only available with ‘-std=c++20’ or ‘-fconcepts’
   37 | void debug(auto &&...x){
      |            ^~~~
answer.code: In function ‘void debug(auto:1&& ...)’:
answer.code:38:21: warning: fold-expressions only available with ‘-std=c++17’ or ‘-std=gnu++17’ [-Wc++17-extensions]
   38 |     ((cerr<<x<<' '),...);
      |                     ^~~
answer.code: In lambda function:
answer.code:70:18: warning: structured bindings only available with ‘-std=c++17’ or ‘-std=gnu++17’ [-Wc++17-extensions]
   70 |         for(auto [v,w]:e[u]){
      |                  ^
answer.code: In lambda function:
answer.code:82:18: warning: structured bindings only available with ‘-std=c++17’ or ‘-std=gnu++17’ [-Wc++17-extensions]
   82 |         for(auto [v,w]:e[u]){
      |                  ^
answer.code: In function ‘int build(long long int, long long int)’:
answer.code:89:14: warning: structured bindings only available with ‘-std=c++17’ or ‘-std=gnu++17’ [-Wc++17-extensions]
   89 |     for(auto [v,w]:e[rt]){
      |              ^
/usr/bin/ld: /tmp/ccbZ3MyC.o: in function `my_assert(bool, int)':
answer.code:(.text+0x1810): multiple definition of `my_assert(bool, int)'; /tmp/cc0SLWiB.o:implementer.cpp:(.text+0x40): first defined here
/usr/bin/ld: /tmp/ccbZ3MyC.o: in function `main':
answer.code:(.text.startup+0x0): multiple definition of `main'; /tmp/cc0SLWiB.o:implementer.cpp:(.text.startup+0x0): first defined here
collect2: error: ld returned 1 exit status