/** * Copyright (c) Microsoft Corporation. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ export function findRepeatedSubsequences(s: string[]): { sequence: string[]; count: number }[] { const n = s.length; const result = []; let i = 0; const arraysEqual = (a1: string[], a2: string[]) => { if (a1.length !== a2.length) return false; for (let j = 0; j < a1.length; j++) { if (a1[j] !== a2[j]) return false; } return true; }; while (i < n) { let maxRepeatCount = 1; let maxRepeatSubstr = [s[i]]; // Initialize with the element at index i let maxRepeatLength = 1; // Try substrings of length from 1 to the remaining length of the array for (let p = 1; p <= n - i; p++) { const substr = s.slice(i, i + p); // Extract substring as array let k = 1; // Count how many times the substring repeats consecutively while ( i + p * k <= n && arraysEqual(s.slice(i + p * (k - 1), i + p * k), substr) ) k += 1; k -= 1; // Adjust k since it increments one extra time in the loop // Update the maximal repeating substring if necessary if (k > 1 && (k * p) > (maxRepeatCount * maxRepeatLength)) { maxRepeatCount = k; maxRepeatSubstr = substr; maxRepeatLength = p; } } // Record the substring and its count result.push({ sequence: maxRepeatSubstr, count: maxRepeatCount }); i += maxRepeatLength * maxRepeatCount; // Move index forward } return result; }