View Compilation Error

0_0_38036858_24488.cpp: In function 'bool check(int)':
0_0_38036858_24488.cpp:14:14: error: expected unqualified-id before '[' token
         auto [l, r] = g[i];
              ^
0_0_38036858_24488.cpp:15:16: error: 'l' was not declared in this scope
         PH += (l - last) * b;
                ^
0_0_38036858_24488.cpp:16:16: error: 'r' was not declared in this scope
         PH -= (r - l) * a;
                ^