View Compilation Error

0_0_38069847_12309.cpp: In function 'long long int tarjan(Graph&)':
0_0_38069847_12309.cpp:49:19: error: expected unqualified-id before '[' token
         for(auto& [to] : g1.graph[i])
                   ^
0_0_38069847_12309.cpp:49:19: error: expected ';' before '[' token
0_0_38069847_12309.cpp:49:20: error: 'to' was not declared in this scope
         for(auto& [to] : g1.graph[i])
                    ^
0_0_38069847_12309.cpp: In lambda function:
0_0_38069847_12309.cpp:49:24: error: expected '{' before ':' token
         for(auto& [to] : g1.graph[i])
                        ^
0_0_38069847_12309.cpp: In function 'long long int tarjan(Graph&)':
0_0_38069847_12309.cpp:49:24: error: expected ';' before ':' token
0_0_38069847_12309.cpp:49:24: error: expected primary-expression before ':' token
0_0_38069847_12309.cpp:49:24: error: expected ')' before ':' token
0_0_38069847_12309.cpp:49:24: error: expected primary-expression before ':' token