/*
Generate N random 1s in a zero-based matrix.
Strategy:
- Treat the matrix as a flat index space [0 .. rows*cols - 1].
- Randomly pick unique positions using a Set to ensure uniqueness.
- Convert each chosen flat index back to (row, col).
- This avoids repeatedly searching for empty cells and keeps the logic simple.
*/
// Allocate a rows×cols matrix initialized to zero
function allocateMatrix(rows, cols) {
// Array.from keeps the code expressive and clear
return Array.from({ length: rows }, () => Array(cols).fill(0));
}
// Print the matrix
function printMatrix(matrix) {
for (const row of matrix) {
console.log(row.join(" "));
}
}
// Generate N random 1s in a zero-based matrix
function generateRandomMatrix(rows, cols, count) {
const total = rows * cols;
if (count > total) {
throw new Error("Requested more 1s than available cells.");
}
const matrix = allocateMatrix(rows, cols);
// Use a Set to ensure unique positions
const chosen = new Set();
// Draw unique positions
while (chosen.size < count) {
const index = Math.floor(Math.random() * total);
chosen.add(index);
}
// Convert flat indices to (row, col)
for (const index of chosen) {
const r = Math.floor(index / cols);
const c = index % cols;
matrix[r][c] = 1;
}
return matrix;
}
// Example usage
const rows = 5;
const cols = 7;
const numberOfOnes = 10;
const result = generateRandomMatrix(rows, cols, numberOfOnes);
printMatrix(result);
/*
run:
0 0 1 0 0 1 0
0 0 0 0 1 0 1
0 1 1 0 0 0 0
1 0 0 1 0 0 0
1 0 1 0 0 0 0
*/
