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<?php $str = <<<STR Featuring six amazing National Parks: Glacier, Waterton Lakes, Yellowstone, Grand Teton, Arches, and Canyonlands. Your tour begins in Chicago where you will board the Empire Builder bound for the first National Park on your trip, Glacier, where you will explore the famed Going-to-the-Sun Road and enjoy a full-day excursion to Waterton Lakes National Park in Canada (passport required). STR; $newStr = preg_replace('/(^|[^\R])\R(?!\R)/u', '', $str); echo $newStr;
Output for 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Warning: preg_replace(): Compilation failed: escape sequence is invalid in character class at offset 6 in /in/mBEdd on line 13
Output for 4.4.6 - 4.4.9, 5.2.2 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.38, 7.0.0 - 7.0.31, 7.1.0 - 7.1.23, 7.2.0 - 7.2.33, 7.3.12 - 7.3.33
Featuring six amazing National Parks: GlacierWaterton Lakes, Yellowstone, Grand Teton, Arches, and Canyonlands.Your tour begins in Chicago where you will boarthe Empire Buildebound for the first National Park on your trip, Glacier, where you will explore the famed Going-to-the-Sun Road and enjoy a full-day excursion tWaterton Lakes National Park in Canada (passport required).
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.5, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.1
Featuring six amazing National Parks: Glacier, Waterton Lakes, Yellowstone, Grand Teton, Arches, and Canyonlands. Your tour begins in Chicago where you will board the Empire Builder bound for the first National Park on your trip, Glacier, where you will explore the famed Going-to-the-Sunoad and enjoy a full-day excursion to Waterton Lakes National Park in Canada (passport required).

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305.97 ms | 403 KiB | 413 Q