Fix string issues for multithreading
Fix string issues for multithreading

or-tools/or-tools,google/or-tools,google/or-tools,or-tools/or-tools,google/or-tools,google/or-tools,google/or-tools,google/or-tools,or-tools/or-tools,or-tools/or-tools,or-tools/or-tools,or-tools/or-tools