View Compilation Error

0_0_8598283_9967.cpp: In function `void ing(char*, char*, int)':
0_0_8598283_9967.cpp:44: error: `strrev' undeclared (first use this function)
0_0_8598283_9967.cpp:44: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_8598283_9967.cpp: In function `int main()':
0_0_8598283_9967.cpp:54: error: `strrev' undeclared (first use this function)