View Compilation Error

0_0_26600737_22557.cpp: In function 'void init(int)':
0_0_26600737_22557.cpp:70:35: error: 'memset' was not declared in this scope
     memset(first, 0, sizeof(first));
                                   ^
0_0_26600737_22557.cpp: In function 'int main()':
0_0_26600737_22557.cpp:106:23: error: 'sort' was not declared in this scope
         sort(ns,ns + m);
                       ^