window.ENTITIES={'/api/snippets/javascript/javascript%20-%20multiply%20two%20matrixes':[{"result":true,"message":null,"batch":{"type":"javascript","name":"javascript - multiply two matrixes","items":[{"id":"Dd5Knp","type":"javascript","name":"JavaScript - multiply two matrixes","content":"// ONLINE-RUNNER:browser;\n\nconst createMatrix = (width, height, creator = () => 0) => {\n    const result = new Array(height);\n    for (let y = 0; y < height; ++y) {\n        const row = new Array(width);\n        for (let x = 0; x < width; ++x) {\n            row[x] = creator(x, y);\n        }\n        result[y] = row;\n    }\n    return result;\n};\n\nconst findWidth = (matrix) => {\n    if (matrix.length > 0) {\n        const row = matrix[0];\n        if (row) {\n            return row.length;\n        }\n    }\n    return 0;\n};\n\nconst findHeight = (matrix) => {\n    return matrix.length;\n};\n\nconst multiplyMatrixes = (a, b) => {\n    const length = findWidth(a);\n    if (length !== findHeight(b)) {\n        throw new Error('Matrixes can not be multipled.');\n    }\n    const width = findWidth(b);\n    const height = findHeight(a);\n    const result = createMatrix(width, height);\n    for (let y = 0; y < height; ++y) {\n        const row = result[y];\n        for (let x = 0; x < width; ++x) {\n            let value = 0;\n            for (let i = 0; i < length; ++i) {\n                value += a[y][i] * b[i][x];\n            }\n            row[x] = value;\n        }\n    }\n    return result;\n};\n\n\n// Usage example:\n\nconst a = [\n\t[1, 2],\n\t[4, 5],\n\t[7, 8]\n];\n\nconst b = [\n\t[1, 2, 3],\n\t[4, 5, 6]\n];\n\nconst c = multiplyMatrixes(a, b);\n\nconsole.log(c);\n\n\n// Output:\n//\n//     [ 9, 12, 15],\n//     [24, 33, 42],\n//     [39, 54, 69]","source":"","author":{"id":"xaOmA0","name":"Lily","avatar":"1629130172536__xaOmA0__w40px_h40px.jpg","points":548,"role":"BASIC"},"creationTime":1703112235000,"updateTime":1703116512000,"removalTime":null}]}}]};