I have a file which contains 10^3 characters. My file looks like:

```
ATTGC
CTGGC
TTTGC
GCTCT

```

I want a file which have all these character in a row with position like as follows:

```
1 A
2 T
3 T
4 G
5 C
6 C
7 T

```

till end.
I tried by vi command line but didn't get result for large file. Is this possible in R.