学姐又去谷歌

学姐又要去Google上班了，这一次学姐想多做几道水题，并使题目的总水量最大.学姐同一时刻只能在水一道题，只有做完这道题才能得到它的水值，学姐的总时间为t，现在一共有n道题，编号从1到n，每道题有两个值a和b，a为做这道题需要的时间，b为题目的水值。

<span style="color:#333333;font-family:Arial;font-size:14.3999996185303px;line-height:26px;background-color:#FFFFFF;">数据中第一行为两个数</span><span class="MathJax_Preview" style="font-family:Arial;font-size:14.3999996185303px;line-height:26px;color:#888888;background-color:#FFFFFF;"></span><span id="MathJax-Span-33" class="math"><span id="MathJax-Span-34" class="mrow">t</span></span><span style="color:#333333;font-family:Arial;font-size:14.3999996185303px;line-height:26px;background-color:#FFFFFF;">和</span><span class="MathJax_Preview" style="font-family:Arial;font-size:14.3999996185303px;line-height:26px;color:#888888;background-color:#FFFFFF;"></span><span id="MathJax-Span-36" class="math"><span id="MathJax-Span-37" class="mrow">n</span></span><span style="color:#333333;font-family:Arial;font-size:14.3999996185303px;line-height:26px;background-color:#FFFFFF;">，</span><span class="MathJax_Preview" style="font-family:Arial;font-size:14.3999996185303px;line-height:26px;color:#888888;background-color:#FFFFFF;"></span><span id="MathJax-Span-39" class="math"><span id="MathJax-Span-40" class="mrow">n</span></span><span style="color:#333333;font-family:Arial;font-size:14.3999996185303px;line-height:26px;background-color:#FFFFFF;">为题目的数量，</span><span class="MathJax_Preview" style="font-family:Arial;font-size:14.3999996185303px;line-height:26px;color:#888888;background-color:#FFFFFF;"></span><span id="MathJax-Span-42" class="math"><span id="MathJax-Span-43" class="mrow">t</span></span><span style="color:#333333;font-family:Arial;font-size:14.3999996185303px;line-height:26px;background-color:#FFFFFF;">为总时间,接下来</span><span class="MathJax_Preview" style="font-family:Arial;font-size:14.3999996185303px;line-height:26px;color:#888888;background-color:#FFFFFF;"></span><span id="MathJax-Span-45" class="math"><span id="MathJax-Span-46" class="mrow">n</span></span><span style="color:#333333;font-family:Arial;font-size:14.3999996185303px;line-height:26px;background-color:#FFFFFF;">行,每行两个正整数</span><span class="MathJax_Preview" style="font-family:Arial;font-size:14.3999996185303px;line-height:26px;color:#888888;background-color:#FFFFFF;"></span><span id="MathJax-Span-48" class="math"><span id="MathJax-Span-49" class="mrow">a<span><span style="font-size:14.3999996185303px;line-height:26px;background-color:#FFFFFF;">和</span></span></span></span><span id="MathJax-Span-51" class="math"><span id="MathJax-Span-52" class="mrow">b</span></span><span style="color:#333333;font-family:Arial;font-size:14.3999996185303px;line-height:26px;background-color:#FFFFFF;">。</span><span class="MathJax_Preview" style="font-family:Arial;font-size:14.3999996185303px;line-height:26px;color:#888888;background-color:#FFFFFF;"></span><span id="MathJax-Span-54" class="math"><span id="MathJax-Span-55" class="mrow"><span id="MathJax-Span-56" class="mo">(</span><span id="MathJax-Span-57" class="mn">1</span><span id="MathJax-Span-58" class="mo">≤</span><span id="MathJax-Span-59" class="mi">a</span><span id="MathJax-Span-60" class="mo">,</span><span id="MathJax-Span-61" class="mi">t</span><span id="MathJax-Span-62" class="mo">≤</span><span id="MathJax-Span-63" class="mn">1000</span><span id="MathJax-Span-64" class="texatom"><span id="MathJax-Span-65" class="mrow"><span id="MathJax-Span-66" class="mo">，</span></span></span><span id="MathJax-Span-67" class="mn">1</span><span id="MathJax-Span-68" class="mo">≤</span><span id="MathJax-Span-69" class="mi">n</span><span id="MathJax-Span-70" class="mo">≤</span><span id="MathJax-Span-71" class="mn">100</span><span id="MathJax-Span-72" class="texatom"><span id="MathJax-Span-73" class="mrow"><span id="MathJax-Span-74" class="mo">，</span></span></span><span id="MathJax-Span-75" class="mn">1</span><span id="MathJax-Span-76" class="mo">≤</span><span id="MathJax-Span-77" class="mi">b</span><span id="MathJax-Span-78" class="mo">≤</span><span id="MathJax-Span-79" class="mn">1000000</span><span id="MathJax-Span-80" class="mo">)</span></span></span>

<span style="color:#333333;font-family:Arial;font-size:14.3999996185303px;line-height:26px;background-color:#FFFFFF;">输出对应的最大总水量。</span>