View Compilation Error

0_0_17022468_26041.cpp:4:1: error: 'usingnamespace' does not name a type
 usingnamespace std;
 ^
0_0_17022468_26041.cpp: In function 'bool dfs(int)':
0_0_17022468_26041.cpp:21:11: error: 'returntrue' was not declared in this scope
 if(th==0) returntrue;
           ^
0_0_17022468_26041.cpp:22:15: error: 'returnfalse' was not declared in this scope
 if(d+th>deep) returnfalse;
               ^
0_0_17022468_26041.cpp:36:14: error: 'returntrue' was not declared in this scope
 if(dfs(d+1)) returntrue;
              ^
0_0_17022468_26041.cpp:42:1: error: 'returnfalse' was not declared in this scope
 returnfalse;
 ^