<p class="ql-block">1</p> <p class="ql-block">13</p><p class="ql-block">1—13</p> <p class="ql-block">（13）+23=36</p> <p class="ql-block">36</p><p class="ql-block">13+23=36</p> <p class="ql-block">36</p><p class="ql-block">36+18=54</p> <p class="ql-block">54</p><p class="ql-block">36+18=54</p> <p class="ql-block">54+45=99</p>