View Compilation Error

281156_0_23779.cpp:2: error: `string' does not name a type
281156_0_23779.cpp: In function `int main()':
281156_0_23779.cpp:2: error: `cin' undeclared (first use this function)
281156_0_23779.cpp:2: error: (Each undeclared identifier is reported only once for each function it appears in.)
281156_0_23779.cpp:2: error: `e' undeclared (first use this function)
281156_0_23779.cpp:2: error: `f' undeclared (first use this function)
281156_0_23779.cpp:2: error: `a' undeclared (first use this function)
281156_0_23779.cpp:2: error: `b' undeclared (first use this function)
281156_0_23779.cpp:2: error: `cout' undeclared (first use this function)
281156_0_23779.cpp:2: error: `endl' undeclared (first use this function)