View Compilation Error

0_0_6673860_27327.cpp: In function `void run()':
0_0_6673860_27327.cpp:96: error: `last' undeclared (first use this function)
0_0_6673860_27327.cpp:96: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_6673860_27327.cpp:103: error: `nw' undeclared (first use this function)