How to output string second word first letter? - c++

Question

I need solution for this code, its almost done, but i dont understand how i can get first letter from second word, not first? In this code i get 1st letter of first word and dont know how to fix, to get first letter from second word of string which is input from user.
#include <iostream>
#include <string>
using namespace std;
int main()
{
string s, krt;
int sk;
cout << "Enter Array: ";
getline(cin, s);
sk = s.length();
cout << "Character in string: " << sk << endl;
int i, vst = 0, bas = 0;
for (i = 0; i < sk; i++) {
krt = s.substr(i, 1);
if (krt == " ")
vst = vst + 1;
}
cout << "Spaces count in string: " << vst << endl;
char tpb;
tpb = s[0];
int pbk;
pbk = tpb;
cout << "String second word first letter: " << tpb << " and its ASCII code: " << pbk << endl;
return 0;
}
Hope you understand what i need to get.

Answer 1

The main problem is that you use 0 as the index, instead of storing the index you want; the first non-space character that follows a space. At least, that is the definition I am going to assume - you didn't specify what to do for multiple consequetive spaces, nor strings containing non-alphabetic characters, such as "function()", where vim would say that '(' is the first character of the second word. Extending the code below to do that is left as an excercise to the reader.
There are a lot of other issues in your code; declarations that can be joined with the definition, doing a string comparison where you only need to compare a single character, and using for loops where there are algorithms to choose instead. Together these add a lot of noise to the code.
Finally, you need some code to handle the case of not having a second word, in order to not get undefined behaviour as in #Diodacus's code.
With regular for-loops:
#include <iostream>
#include <string>
using namespace std;
int main()
{
string s;
cout << "Enter Array: ";
getline(cin, s);
const int sk = s.length();
cout << "Character in string: " << sk << endl;
int vst = 0;
bool space_has_passed = false;
int first_nonspace_after_space_index = -1;
for (int i = 0; i < sk; i++) {
if (s[i] == ' ') {
vst = vst + 1;
space_has_passed = true;
} else if (space_has_passed && first_nonspace_after_space_index == -1) {
first_nonspace_after_space_index = i;
}
}
cout << "Spaces count in string: " << vst << endl;
if ( first_nonspace_after_space_index != -1 && sk > first_nonspace_after_space_index) {
const char tpb = s[first_nonspace_after_space_index];
const int pbk = tpb;
cout << "String second word first letter: " << tpb << " and its ASCII code: " << pbk << endl;
} else {
cout << "Need at least two words" << endl;
}
return 0;
}
You can cut it down by 7 lines if you use <algorithms>:
#include <iostream>
#include <string>
#include <algorithm>
using namespace std;
int main()
{
string s;
cout << "Enter Array: ";
getline(cin, s);
const int sk = s.length();
cout << "Character in string: " << sk << endl;
auto first_space = std::find(s.begin(), s.end(), ' ');
auto first_nonspace_afterspace = std::find_if(++first_space, s.end(), [](const char & c){ return c != ' '; });
int count_spaces = std::count(s.begin(), s.end(), ' ');
cout << "Spaces count in string: " << count_spaces << endl;
if( first_nonspace_afterspace != s.end() ) {
const char tpb = *first_nonspace_afterspace;
const int pbk = tpb;
cout << "String second word first letter: " << tpb << " and its ASCII code: " << pbk << endl;
} else {
cout << "Need at least two words" << endl;
}
return 0;
}

Answer 2

I suggest you to take a brief look at the string class documentation page (http://www.cplusplus.com/reference/string/string/), there is a lot of function that can help you manipulate string.
Based on the functions available in this class (eg. cbegin(), cend(), find(), c_str(), etc.), you could do something like this:
#include <iostream>
#include <string>
#include <ctype.h>
using namespace std;
int main()
{
string s;
cout << "Enter array: ";
getline(cin, s);
int sk = s.length();
cout << "Character in string: " << sk << endl;
int vst = 0;
for (auto i=s.cbegin(); i!=s.cend(); ++i)
if(isspace(*i)) vst++;
cout << "Spaces count in string: " << vst << endl;
string t = s.substr(s.find(" ") + 1, 1);
char tpb = *t.c_str();
int pkt = tpb;
cout << "String second word first letter: " << tpb << " and its ASCII code: " << pkt << endl;
return 0;
}
The main problem is that you print the first letter of the string passed in parameter:
tpb = s[0];
You should either:
memorize the index of the location of the first char of the second word
or
get the second word of the string passed in parameter and print the first char of this string
Finally, what is happening when there is only one word passed ?
You should also think about that. In the code above, if you pass the word test the program prints anyway String second word first letter: t and its ASCII code: 116 which is not true.

Answer 3

Try this:
#include <iostream>
#include <string>
using namespace std;
int main ()
{
string s, krt;
int sk;
cout << "Enter Array: ";
getline (cin, s);
sk = s.length();
cout << "Character in string: " << sk << endl;
int i, vst = 0, bas = 0;
for (i = 0; i < sk; i++)
{
krt = s.substr(i, 1);
if (krt == " ") vst = vst + 1;
}
cout << "Spaces count in string: " << vst << endl;
char tpb;
for (i = 0; i < sk; ++i) // Searching for first space
{
if (s[i] == ' ')
break;
}
tpb = s[i + 1];
int pbk;
pbk = tpb;
cout << "String second word first letter: " << tpb << " and its ASCII code: " << pbk << endl;
return 0;
}
This should do the trick.