c++ array error while executing -

when run program keep getting error. program still execute , run , display correct nymbers in terminal, need ouput file , put them on there. please new c++.

bash-3.2$ g++ -wall 1.cpp
1.cpp: in function 'std::string ip_calculation(std::string*, std::string, int)':1.cpp:71:1: warning: control reaches end of non-void function [-wreturn-type]

---

string ip_calculation(string ip[], string company_name, int total_ips) {     string temp = "";     char buf[80];     char buf2[80];     if (total_ips != 0)     {         int uniqueip_count = total_ips;          (int = 0; < total_ips; i++)         {             (int j = + 1; j < total_ips; j++)             {                  if (strcmp(ip[i].c_str(), ip[j].c_str()) == 0)                 {                     if (strcmp(ip[i].c_str(), "") == 0)                     {                         continue;                     }                      ip[j] = "";                     uniqueip_count--;                  }              }          }          temp = print_array(ip);          cout << company_name << " | number of visitor: " << total_ips                 << "| unique         visitors: " << uniqueip_count << endl;         //cout<<company_name<<" | number of visitor: "<<buf <<"| unique  visitors:      "<<uniqueip_count<<endl;         cout << temp;         sprintf(buf, "%d", total_ips);         sprintf(buf2, "%d", uniqueip_count);         // return temp=company_name+" | number of visitor: "+( total_ips) +"|      unique   visitors: "+to_string( uniqueip_count)+"\n"+temp+"\n";         return temp = company_name + " | number of visitor: " + buf                 + "| unique   visitors:   " + buf2 + "\n" + temp + "\n";     } } 

the warning because function declared return string, compiler has determined it's possible may not that. have return statement returns string in if statement. when total_ips 0, won't execute block of code, , you'll never execute return statement. since don't have else block, you'll exit function, without returning string required. need change to:

if (total_ips != 0) {     ... } else {     return ""; } 

so return when condition fails.