View Compilation Error

0_0_15359976_22375.cpp: In function 'int main()':
0_0_15359976_22375.cpp:5:17: error: 'gets' was not declared in this scope
     while(gets(c)&&c[0]!='#')
                 ^
0_0_15359976_22375.cpp:8:37: error: 'strlen' was not declared in this scope
         for(int j = 0 ; j < strlen(c) ; j++)
                                     ^
0_0_15359976_22375.cpp:13:9: error: 'cout' was not declared in this scope
         cout<<total<<endl;
         ^
0_0_15359976_22375.cpp:13:22: error: 'endl' was not declared in this scope
         cout<<total<<endl;
                      ^