View Compilation Error

0_0_37866805_31460.cpp: In function 'int algorithm()':
0_0_37866805_31460.cpp:9:5: error: expected initializer before 'double'
     double a,b,c;
     ^
0_0_37866805_31460.cpp:10:10: error: 'n' was not declared in this scope
     cin>>n;
          ^
0_0_37866805_31460.cpp:12:14: error: 'a' was not declared in this scope
         cin>>a>>b>>c;
              ^
0_0_37866805_31460.cpp:12:17: error: 'b' was not declared in this scope
         cin>>a>>b>>c;
                 ^
0_0_37866805_31460.cpp:12:20: error: 'c' was not declared in this scope
         cin>>a>>b>>c;
                    ^