View Compilation Error

0_0_21215097_3359.cpp: In function 'int main()':
0_0_21215097_3359.cpp:9:27: error: 'memset' was not declared in this scope
   memset(pop,0,sizeof(pop));
                           ^
0_0_21215097_3359.cpp:19:32: error: 'strcmp' was not declared in this scope
     if(strcmp(color[i],color[j])==0)
                                ^
0_0_21215097_3359.cpp:34:29: error: 'strcpy' was not declared in this scope
     strcpy(pop[x++],color[i]);
                             ^
0_0_21215097_3359.cpp:44:23: error: 'strcpy' was not declared in this scope
      strcpy(str,pop[i]);
                       ^