View Compilation Error

0_0_25103581_29869.cpp: In function 'int main()':
0_0_25103581_29869.cpp:15:25: error: 'memset' was not declared in this scope
   memset(dp,0,sizeof(dp));
                         ^
0_0_25103581_29869.cpp:17:21: error: 'strlen' was not declared in this scope
   int len1=strlen(s1);
                     ^