title: 2 variables in a for loop in R
body: <p>I have two vectors that I would like to reference in a for loop, but each is of different lengths.</p>
  
  <pre><code>n=1:50
  m=letters[1:14]
  </code></pre>
  
  <p>I tried a single loop to read it</p>
  
  <pre><code>for (i in c(11:22,24,25)){
      cat (paste(n[i],m[i],sep='\t'),sep='\n')
  }
  </code></pre>
  
  <p>and ended up with:</p>
  
  <pre><code>11  k
  12  l
  13  m
  14  n
  15  NA
  16  NA
  17  NA
  18  NA
  19  NA
  20  NA
  21  NA
  22  NA
  24  NA
  25  NA
  </code></pre>
  
  <p>but I would like to obtain:</p>
  
  <pre><code>11  a
  12  b
  13  c
  ...
  25  n
  </code></pre>
  
  <p>is there a way to have a double variable declaration?</p>
  
  <pre><code>for (i in c(11:22,24,25) and j in 1:14){
      cat (paste(n[i],m[j],sep='\t'),sep='\n')
  }
  </code></pre>
  
  <p>or something similar to get the result I want?</p>