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#!/usr/local/bin/node
//
// See ../README.md
//
//
// Run as: node ch-2.js < input-file
//
let SIZE = 7
let printf = require ('printf')
require ('readline')
. createInterface ({input: process . stdin})
. on ('line', _ => main (_ . split (/\s+/) . map (_ => +_)))
;
function main (numbers) {
//
// First, we create a datastructure to collect all the
// differences between two numbers, with the restriction
// that the difference is present in numbers
//
let differences = {}
numbers . forEach (n => differences [n] = [])
numbers . forEach ((x, x_i) => {
numbers . forEach ((y, y_i) => {
if (x_i != y_i) {
let diff = x - y
if (differences [diff]) {
differences [diff] . push ([x_i, y_i])
}
}
})
})
//
// For each number d in numbers, with index d_i, find all pairs
// of distinct numbers, all with index other than d_i, where the
// differences of each pair is d.
//
numbers . forEach ((d, d_i) => {
let diffs = differences [d]
for (let x = 0; x < diffs . length; x ++) {
//
// Ignore any difference involving d_i
//
if (diffs [x] [0] == d_i || diffs [x] [1] == d_i) {
continue
}
for (let y = x + 1; y < diffs . length; y ++) {
//
// Second diff should not involve d_i, and all its
// elemenst should be different from the first diff
//
if (diffs [y] [0] == d_i || diffs [y] [1] == d_i ||
diffs [x] [0] == diffs [y] [0] ||
diffs [x] [0] == diffs [y] [1] ||
diffs [x] [1] == diffs [y] [0] ||
diffs [x] [1] == diffs [y] [1]) {
continue
}
//
// W.l.o.g we can now assume diff [x] gives us a_i and c_i,
// and diff [y] gives use g_i and e_i
//
let [a_i, c_i] = diffs [x]
let [g_i, e_i] = diffs [y]
//
// Find the two possibilities for b_i and f_i
//
for (let b_i = 0; b_i < numbers . length; b_i ++) {
if (b_i == a_i || b_i == c_i || b_i == d_i ||
b_i == e_i || b_i == g_i) {
continue
}
for (let f_i = 0; f_i < numbers . length; f_i ++) {
if (f_i == a_i || f_i == b_i || f_i == c_i ||
f_i == d_i || f_i == e_i || f_i == g_i) {
continue
}
//
// Do we have a winner?
//
let target = numbers [a_i] + numbers [b_i]
if (target == numbers [b_i] + numbers [c_i] +
numbers [d_i] &&
target == numbers [d_i] + numbers [e_i] +
numbers [f_i] &&
target == numbers [f_i] + numbers [g_i]) {
//
// Print the results, and the reverse
//
printf (process . stdout, "%d %d %d %d %d %d %d\n",
numbers [a_i], numbers [b_i],
numbers [c_i], numbers [d_i],
numbers [e_i], numbers [f_i],
numbers [g_i])
printf (process . stdout, "%d %d %d %d %d %d %d\n",
numbers [g_i], numbers [f_i],
numbers [e_i], numbers [d_i],
numbers [c_i], numbers [b_i],
numbers [a_i])
}
}
}
}
}
})
}
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