View Compilation Error

0_0_12043090_26940.cpp:6: error: `main' must return `int'
0_0_12043090_26940.cpp: In function `int main(...)':
0_0_12043090_26940.cpp:16: error: `itoa' undeclared (first use this function)
0_0_12043090_26940.cpp:16: error: (Each undeclared identifier is reported only once for each function it appears in.)