View Compilation Error

0_0_17136560_29993.cpp: In function 'void format(char*)':
0_0_17136560_29993.cpp:35:30: error: 'strlen' was not declared in this scope
  int i=0,j,len=0,n=strlen(dst);
                              ^
0_0_17136560_29993.cpp: In function 'int main()':
0_0_17136560_29993.cpp:84:29: error: 'strcpy' was not declared in this scope
     strcpy(dst,text[j].title);
                             ^
0_0_17136560_29993.cpp:87:23: error: 'strstr' was not declared in this scope
     if (strstr(dst,src))
                       ^