770. Word replacement

subject

Enter a string , End with a carriage return （ The string length does not exceed 100）.

The string consists of several words , Words are separated by a space , All words are case sensitive .

Now we need to replace one word with another , And output the replaced string .

Input format
Input common 3 That's ok .

The first 1 A line is a string containing multiple words s;

The first 2 Line is the word to be replaced a( Length not exceeding 100);

The first 3 Line is a The word to be replaced b( Length not exceeding 100).

Output format
All in one line , The output will s All words in a Replace with b String after .

sample input ：
You want someone to help you
You
I
sample output ：
I want someone to help you

Code

#include <iostream>
#include <sstream> // needed stringstream The header file 

using namespace std;

int main()
{
    
    string s, a, b;
    
    getline(cin, s);
    cin >> a >> b;
    
    stringstream ssin(s);// Convert string to character stream , after ssin Be similar to cin, The difference is that ssin You can stream from the specified character s Read string from 
    
    string tmp;// Store temporary slave character streams s String read from 
    while(ssin >> tmp)// Always stream from character stream s Read the string to tmp in 
        if(tmp == a) cout << b << ' ';// If tmp == a, The output b
        else cout << tmp << ' ';// Otherwise, the original string is output 
    
    
    return 0;
}