tvl-depot/scratch/deepmind/part_two/merge-sorted-arrays.ts

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function mergeArrays(xs: Array<number>, ys: Array<number>): Array<number> {
let i = 0;
let j = 0;
const result = [];
for (let q = 0; q < xs.length + ys.length; q += 1) {
if (i === xs.length) {
while (j < ys.length) {
result.push(ys[j]);
j += 1;
}
} else if (j === ys.length) {
while (i < xs.length) {
result.push(xs[i]);
i += 1;
}
} else if (xs[i] < ys[j]) {
result.push(xs[i]);
i += 1;
} else {
result.push(ys[j]);
j += 1;
}
}
return result;
}
// Tests
let desc = "both arrays are empty";
let actual = mergeArrays([], []);
let expected = [];
assertDeepEqual(actual, expected, desc);
desc = "first array is empty";
actual = mergeArrays([], [1, 2, 3]);
expected = [1, 2, 3];
assertDeepEqual(actual, expected, desc);
desc = "second array is empty";
actual = mergeArrays([5, 6, 7], []);
expected = [5, 6, 7];
assertDeepEqual(actual, expected, desc);
desc = "both arrays have some numbers";
actual = mergeArrays([2, 4, 6], [1, 3, 7]);
expected = [1, 2, 3, 4, 6, 7];
assertDeepEqual(actual, expected, desc);
desc = "arrays are different lengths";
actual = mergeArrays([2, 4, 6, 8], [1, 7]);
expected = [1, 2, 4, 6, 7, 8];
assertDeepEqual(actual, expected, desc);
function assertDeepEqual(a: Array<number>, b: Array<number>, desc: string) {
const aStr = JSON.stringify(a);
const bStr = JSON.stringify(b);
if (aStr !== bStr) {
console.log(`${desc} ... FAIL: ${aStr} != ${bStr}`);
} else {
console.log(`${desc} ... PASS`);
}
}