View Compilation Error

0_0_26623457_17802.cpp:4:8: error: expected ')' before ';' token
   int a;
        ^
0_0_26623457_17802.cpp:4:8: error: 'main' declared as function returning a function
0_0_26623457_17802.cpp:7:8: error: expected constructor, destructor, or type conversion before '(' token
   scanf(%d,&n);
        ^
0_0_26623457_17802.cpp:8:3: error: expected unqualified-id before 'while'
   while
   ^
0_0_26623457_17802.cpp:14:4: error: expected unqualified-id before 'return'
    return 0;
    ^
0_0_26623457_17802.cpp:15:1: error: expected declaration before '}' token
 }
 ^