View Compilation Error

0_0_2541603_26408.cpp: In function `int main()':
0_0_2541603_26408.cpp:26: error: `itoa' undeclared (first use this function)
0_0_2541603_26408.cpp:26: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_2541603_26408.cpp:27: error: `strupr' undeclared (first use this function)