vector<string> split(const string str,const string delimit){
vector<string> v;
int last_idx=0;
int idx=str.find_first_of(delimit,last_idx);
while(idx != string::npos){
v.push_back(str.substr(last_idx,idx-last_idx));
last_idx=idx+1;
idx = str.find_first_of(delimit,last_idx);
}
if(last_idx<str.size()){
v.push_back(str.substr(last_idx,str.size()-last_idx));
}
return v;
}