Print first and last character of each word in a string

Introduction

A C++ string is contiguous storage of alphanumeric characters as well as special characters. A string has the following properties ?

• Every C++ string is associated with a fixed length.

• Character operations can be easily performed with the string characters.

• A string is composed of words, which are space separated.

In this article, we are going to develop a code that takes as input a string, and displays the last character of each word in the string. Let us look at the following example to understand the topic better ?

Sample Example

Example 1 ?

str ? "Key word of a string"
Output ? Ky wd of aa sg

For instance, in the fourth word of this string, only a single character "a" occurs, therefore this is the first and last character of this string.

In this article, we will develop a code to extract the last character of each word using indexing operator. Here, we will develop a code to extract the last character of each word using indexing operator ,and then accessing the characters at the subsequent previous characters respectively.

Syntax

str.length() 

length()

The length() method in C++ is used to compute the number of characters in the string. The in-built length() method works in linear time.

Algorithm

• An input string, str is accepted.

• The length of the string is computed using the length() method, and stored in the len variable.

• An iteration of the string is performed, using the for loop i.

• The particular character of string is extracted and stored in the variable ch.

• Each time the character at ith position is extracted

• If this index is equivalent to the first index of the string, it is printed

• If this index is equivalent to the last index of the string,then len-1 character, is displayed.

• If this character is equivalent to the space character, then the i-1th index character is displayed, since it is the last character of the previous word.

• The i+1th index is also printed owing to the first character of the next word respectively.

Example

The following C++ code snippet is used to take as input a sample string and compute the first and last character of each word in the string ?

//including the required libraries #include<bits/stdc++.h> using namespace std; //compute the first and last characters of a string void wordfirstandlastchar(string str) { // getting length of the string int len = str.length(); for (int i = 0; i <len ; i++) { char ch = str[i]; //print the first word of the string if (i == 0) cout<<ch; //last word of the string if (i == len - 1) cout<<ch; //if a space is encountered, marks the start of new word if (ch == ' ') { //print the previous character of the last word //print the next character of the next word char lst = str[i-1]; char nxt = str[i+1]; cout<<lst<<" "<<nxt; } } } //calling the method int main() { //taking a sample string string str = "I want to learn at TutorialsPoint"; cout<<"Input String : "<< str <<"\n"; //getfirstandlast characters cout<<"First and last words of each string : \n"; wordfirstandlastchar(str); } 

Output

Input String ? I want to learn at TutorialsPoint First and last words of each string ? II wt to ln at Tt 

Conclusion

Most of the character manipulation operations in C++ strings can be performed using a single traversal of the string. The characters of the string can be easily accessed using their positions in constant time. The indexes of the string begin with 0 and end with the string length-1 value.