$ echo "Lorem ipsum dolor sit amet, consectetur adipiscing elit. Cras id felis lectus. Quisque dictum blandit consequat. Nulla facilisis ante augue, vitae lobortis elit lobortis finibus." > lipsum.txt
$ ./inverted_index lipsum.txt
{
"adipiscing": [40],
"nulla": [113],
"blandit": [94],
"lorem": [0],
"dolor": [12],
"dictum": [87],
"amet": [22],
"ante": [129],
"cras": [57],
"id": [62],
"quisque": [79],
"ipsum": [6],
"elit": [51, 156],
"lobortis": [147, 161],
"consectetur": [28],
"sit": [18],
"lectus": [71],
"finibus": [170],
"felis": [65],
"consequat": [102],
"facilisis": [119],
"augue": [134],
"vitae": [141]
}