I had error in 4_6_tests:
```
Running 2 test cases...
unknown location(0): fatal error in "solution_constructor_tests": xstring(1441) : Assertion failed: string subscript out of range

solutions\pavel_kasko\4\tests\4_6_tests\solution_tests.cpp(41): last checkpoint

*** 1 failure detected in test suite "Master Test Suite"
```