View Compilation Error

0_0_7650473_15845.cpp: In function `int ctoi(char*)':
0_0_7650473_15845.cpp:9: error: `strcmpi' undeclared (first use this function)
0_0_7650473_15845.cpp:9: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_7650473_15845.cpp: In function `int main()':
0_0_7650473_15845.cpp:40: error: `strcmpi' undeclared (first use this function)