View Compilation Error

0_0_37749109_4052.cpp: In function 'int main()':
0_0_37749109_4052.cpp:13:13: error: 'o' was not declared in this scope
   memset(du,o,sizeof du);
             ^
0_0_37749109_4052.cpp:13:24: error: 'memset' was not declared in this scope
   memset(du,o,sizeof du);
                        ^