View Compilation Error

0_0_11307902_18390.cpp: In function `int main()':
0_0_11307902_18390.cpp:24: error: `vis' undeclared (first use this function)
0_0_11307902_18390.cpp:24: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_11307902_18390.cpp:42: error: `ti' undeclared (first use this function)