View Compilation Error

0_0_23218586_38.cpp: In function 'int maintain(int&, bool)':
0_0_23218586_38.cpp:81:5: error: return-statement with no value, in function returning 'int' [-fpermissive]
     return;//??????????
     ^
0_0_23218586_38.cpp:95:5: error: return-statement with no value, in function returning 'int' [-fpermissive]
     return;
     ^