View Compilation Error

0_0_16231302_31640.cpp: In function 'int main()':
0_0_16231302_31640.cpp:65:25: error: 'memset' was not declared in this scope
   memset(tr,0,sizeof(tr));
                         ^
0_0_16231302_31640.cpp:67:2: error: expected ';' before '}' token
  }
  ^