1. (3 points) What is the output of this program? using namespace std; void printString( string s, int first) f for ( int 1= first ;1<5,length();1++) cout s[i] cout endl 3 int endPro( string strExp, int first) f cout""<endl;printString(strExp,first);//Dutputhere//Dutputhere int last = strExp length ()1; if (first <0 |I first > last ) return -1 ; char ch=strExp[first]; if (0<=chkch<=39) return first; else if (ch==,+3ch==31ch== * ,ch==,/3) \{ cout ch endl; // Dutput here int endPos = endPre (strExp, 1irst +1); cout endPos endl; /1 Dutput here if (endPos >1 ) return endPre (strExp, endPos +1); else return -1 ; 3 olse return -1 ; \} int main() [ cout << endPre ("++23+56,0); 3.