View Compilation Error

0_0_4090953_4600.cpp: In function `int main()':
0_0_4090953_4600.cpp:13: error: `strlwr' undeclared (first use this function)
0_0_4090953_4600.cpp:13: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_4090953_4600.cpp:19: error: `strrev' undeclared (first use this function)