title: how to merge columns of multiple excel files in R?
body: <p>I have many Excel files.Every file having same format and number of columns.Suppose, file A containing data </p>
  
  <pre><code>    501 0006232.txt 0006235.txt 502 0.019047619 0.045989773
                      0006236.txt 503 0.042735043 0.116345945
                      0006239.txt 504 0.038095238 0.059372542
                      0006240.txt 505 0.0078125   0.007727828
                      0006247.txt 507 0.051724138 0.082823013
  </code></pre>
  
  <p>similarly, file B containing data </p>
  
  <pre><code>    502 0006235.txt 0006236.txt 503 0.075757576 0.377716498
                      0006239.txt 504 0.01754386  0.043033148
                      0006240.txt 505 0.012987013 0.014002801
                      0006246.txt 506 0.044444444 0.150648715
                      0006247.txt 507 0.044117647 0.105052539
  </code></pre>
  
  <p>Now, I want to merge these files in following way</p>
  
  <pre><code>501 0006232.txt 0006235.txt 502 0.019047619 0.045989773
                  0006236.txt 503 0.042735043 0.116345945
                  0006239.txt 504 0.038095238 0.059372542
                  0006240.txt 505 0.0078125   0.007727828
                  0006247.txt 507 0.051724138 0.082823013
  502 0006235.txt 0006236.txt 503 0.075757576 0.377716498
                  0006239.txt 504 0.01754386  0.043033148
                  0006240.txt 505 0.012987013 0.014002801
                  0006246.txt 506 0.044444444 0.150648715
                  0006247.txt 507 0.044117647 0.105052539
  </code></pre>
  
  <p>But unable to do this. How can i do this ?</p>