View Compilation Error

0_0_30178739_22533.cpp: In function 'int main()':
0_0_30178739_22533.cpp:62:9: error: 'mpx' was not declared in this scope
         mpx.clear();
         ^
0_0_30178739_22533.cpp:63:9: error: 'mpy' was not declared in this scope
         mpy.clear();
         ^