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//
// Read STDIN. Split on newlines, then on whitespace, and turn the results
// into numbers. Since the input will be newline terminated, we have an
// empty line to filter out.
//
let matrix = require ("fs")
. readFileSync (0) // Read a line.
. toString () // Turn it into a string.
. split ("\n") // Split on newlines.
. filter (_ => _) // Remove empty (trailing) line.
. map (_ => _ . split (/\s+/) // Split each line on spaces
. map (_ => +_)); // Turn into numbers.
let height = matrix . length;
let width = matrix [0] . length;
//
// Use a cubic algorithm to count any squares will all 1s at the corners.
// For each 0 <= x < height, 0 <= y < width, and k > 0 such that x + k < height
// and y + k < width, we add a square if all of the following are true:
// matrix [x] [y]
// matrix [x + k] [y]
// matrix [x] [y + k]
// matrix [x + k] [y + k]
//
let count = 0;
for (let x = 0; x < height; x ++) {
for (let y = 0; y < width; y ++) {
if (!matrix [x] [y]) {
continue;
}
for (let k = 1; x + k < height && y + k < width; k ++) {
if (matrix [x] [y + k] &&
matrix [x + k] [y] &&
matrix [x + k] [y + k]) {
count ++
}
}
}
}
//
// Print the result.
//
console . log (count);
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