View Compilation Error

0_0_6984370_13965.cpp:7: error: `constint' does not name a type
0_0_6984370_13965.cpp:8: error: `constint' does not name a type
0_0_6984370_13965.cpp:9: error: `constint' does not name a type
0_0_6984370_13965.cpp: In function `bool dfs(int)':
0_0_6984370_13965.cpp:15: error: `B' undeclared (first use this function)
0_0_6984370_13965.cpp:15: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_6984370_13965.cpp:16: error: `R' undeclared (first use this function)
0_0_6984370_13965.cpp: In function `bool solve()':
0_0_6984370_13965.cpp:39: error: `W' undeclared (first use this function)
0_0_6984370_13965.cpp: In function `int main()':
0_0_6984370_13965.cpp:68: error: `R' undeclared (first use this function)