View Compilation Error

0_0_7911875_9176.cpp:3: error: `usingnamespace' does not name a type
0_0_7911875_9176.cpp: In function `bool dfs(int)':
0_0_7911875_9176.cpp:67: error: `returntrue' undeclared (first use this function)
0_0_7911875_9176.cpp:67: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_7911875_9176.cpp:68: error: `returnfalse' undeclared (first use this function)
0_0_7911875_9176.cpp: At global scope:
0_0_7911875_9176.cpp:91: error: ISO C++ forbids declaration of `voidin' with no type
0_0_7911875_9176.cpp: In function `int main()':
0_0_7911875_9176.cpp:102: error: `in' undeclared (first use this function)