View Compilation Error

0_0_2081795_21293.cpp: In function `int main(int, char**)':
0_0_2081795_21293.cpp:11: error: `cin' undeclared (first use this function)
0_0_2081795_21293.cpp:11: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_2081795_21293.cpp:21: error: `cout' undeclared (first use this function)