<p>Design an algorithm to find all pairs of integers within an array which sum to a specified value.</p> <p><strong>Example 1:</strong></p> <pre> <strong>Input:</strong> nums = [5,6,5], target = 11 <strong>Output: </strong>[[5,6]]</pre> <p><strong>Example 2:</strong></p> <pre> <strong>Input:</strong> nums = [5,6,5,6], target = 11 <strong>Output: </strong>[[5,6],[5,6]]</pre> <p><strong>Note: </strong></p> <ul> <li><code>nums.length <= 100000</code></li> <li><code>-10^5 <= nums[i], target <= 10^5</code></li> </ul>