View Compilation Error

0_0_17008686_20503.cpp: In function 'int main()':
0_0_17008686_20503.cpp:13:45: error: 'memset' was not declared in this scope
 #define clr(x, k) memset((x), (k), sizeof(x))
                                             ^
0_0_17008686_20503.cpp:30:9: note: in expansion of macro 'clr'
         clr(degree, 0);
         ^