View Compilation Error

0_0_18897152_2609.cpp: In function 'void init(myint)':
0_0_18897152_2609.cpp:16:31: error: 'memset' was not declared in this scope
     memset(num, 0, sizeof(num));
                               ^
0_0_18897152_2609.cpp: In function 'int main()':
0_0_18897152_2609.cpp:66:21: error: 'strlen' was not declared in this scope
     len = strlen(str);
                     ^