View Compilation Error

0_0_3127716_19396.cpp: In function `int main()':
0_0_3127716_19396.cpp:173: error: `devices' undeclared (first use this function)
0_0_3127716_19396.cpp:173: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_3127716_19396.cpp:179: error: `obstacles' undeclared (first use this function)
0_0_3127716_19396.cpp: At global scope:
0_0_3127716_19396.cpp:256: error: expected unqualified-id before "return"
0_0_3127716_19396.cpp:256: error: expected `,' or `;' before "return"
0_0_3127716_19396.cpp:257: error: expected declaration before '}' token