View Compilation Error

0_0_18884749_23994.cpp: In function 'int main()':
0_0_18884749_23994.cpp:14:16: error: 'n' was not declared in this scope
    scanf("%d",&n);
                ^
0_0_18884749_23994.cpp:17:14: error: 'sort' was not declared in this scope
    sort(a,a+n);
              ^