#include <iostream>
#include <algorithm>
//********************
// You may NOT add other #includes
// You have to write other desired
// functionality yourself
//********************
using namespace std;
// Complete the following function
//
// This function should return a **new**, correctly-formatted C-String
// with size "length" (given by the input argument) and
// containing the substring from str[startPos] to str[startPos+length-1].
//
// str is a valid C-string. It should not be altered
// startPos starting index/position of the desired substring
// length is the desired length of the substring
//
// Return the pointer (start address) of the new array containing
// the substring. You should always return a pointer to a valid
// C-string even if the input arguments are invalid...see examples
// below.
//
// ** You may NOT use any library functions in your implementation **
//
// Example 1: csubstr("Hello world", 3, 4) should return "lo w"
// Example 2: csubstr("USC", 0, 2) should return "US"
//
// if any part of the specified range of the substring falls out of
// bounds of the input string, return a substring containing only
// the valid portion.
//
// Example 3: csubstr("USC", 1, 10) should return just "SC"
// since the length is beyond the end of "USC"
//
//
char* new_csubstr(char* str, int startPos, int length)
{
int mylen=0;
while(str[mylen] != '\0') mylen++;
// we might waste some memory if `length` characters
// cannot be extracted, but let's use the length given us
char* retval = new char[length+1];
int oidx = 0;
int maxIndex = min(startPos+length, mylen);
for(int i=startPos; i < maxIndex; i++){
retval[oidx] = str[i];
oidx++;
}
retval[oidx] = '\0';
return retval;
}
//**************************************
// Do not change these 2 lines and don't
// add any lines between them and main()
//**************************************
#ifndef AUTO_TEST
#define AUTO_TEST
int main(int argc, char* argv[])
{
//*********************************************************
// Make test calls to your function here
//*********************************************************
char* result;
result = new_csubstr("Hello world", 3, 4);
cout << result << endl;
delete [] result;
result = new_csubstr("USC", 0, 2);
cout << result << endl;
delete [] result;
return 0;
}
//****************************************
// Do not change the following line
//****************************************
#endif
