View Compilation Error

0_0_11630223_669.cpp: In function `int main()':
0_0_11630223_669.cpp:4: error: `cin' undeclared (first use this function)
0_0_11630223_669.cpp:4: error: (Each undeclared identifier is reported only once for each function it appears in.)
0_0_11630223_669.cpp:17: error: `sort' undeclared (first use this function)
0_0_11630223_669.cpp:21: error: `cout' undeclared (first use this function)