View Compilation Error

0_0_39782701_20910.cpp: In function 'void down(long long int, long long int, long long int)':
0_0_39782701_20910.cpp:24:9: error: 'lazy' was not declared in this scope
   24 |         lazy(i << 1, change[i], ln);
      |         ^~~~
0_0_39782701_20910.cpp: In function 'std::pair<long long int, long long int> insert(long long int, long long int)':
0_0_39782701_20910.cpp:81:13: error: 'findZero' was not declared in this scope
   81 |     start = findZero(from, 1);
      |             ^~~~~~~~
At global scope:
cc1plus.exe: error: '::main' must return 'int'