View Compilation Error

0_0_27403690_13347.cpp: In function 'int main()':
0_0_27403690_13347.cpp:5:18: error: 'scanf' was not declared in this scope
     scanf("%d",&n);
                  ^
0_0_27403690_13347.cpp:19:41: error: 'printf' was not declared in this scope
         printf("%.2f%%\n",s[m]*100.0/sum);
                                         ^
0_0_27403690_13347.cpp:21:13: error: expected '}' at end of input
     return 0;
             ^