View Compilation Error

0_0_32590853_27600.cpp: In function 'int main()':
0_0_32590853_27600.cpp:16:2: error: 'cin' was not declared in this scope
  cin>>n>>m;
  ^
0_0_32590853_27600.cpp:22:19: error: 'sort' was not declared in this scope
   sort(e,e+n+1,cmp);
                   ^
0_0_32590853_27600.cpp:33:3: error: 'cout' was not declared in this scope
   cout<<res<<endl;
   ^
0_0_32590853_27600.cpp:33:14: error: 'endl' was not declared in this scope
   cout<<res<<endl;
              ^