View Compilation Error

0_0_6962402_2397.cpp: In function `int main()':
0_0_6962402_2397.cpp:7: error: `cin' undeclared (first use this function)
0_0_6962402_2397.cpp:7: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_6962402_2397.cpp:23: error: `elsed' undeclared (first use this function)
0_0_6962402_2397.cpp:28: error: `cout' undeclared (first use this function)
0_0_6962402_2397.cpp:28: error: `endl' undeclared (first use this function)