View Compilation Error

0_0_33030108_7780.cpp: In function 'int main()':
0_0_33030108_7780.cpp:6:18: error: 'scanf' was not declared in this scope
     scanf("%d",&n);
                  ^
0_0_33030108_7780.cpp:14:42: error: expected primary-expression before '||' token
             else if(a[j]>'A'&&a[j]<='Z'&&||a[j]!='E'||a[j]!='I'||a[j]!='O'||a[j]!='U')
                                          ^
0_0_33030108_7780.cpp:17:15: error: 'puts' was not declared in this scope
         puts(a);
               ^