❐<input type="text" id="input1" placeholder="输入正整数" value="2" />
<input type="text" id="input2" placeholder="输入正整数" value="3" />
<button onclick="output.innerHTML = new BigNumber(input1.value).add(input2.value)">求和</button>
<button onclick="output.innerHTML = new BigNumber(input1.value).sub(input2.value)">求差</button>
<button onclick="output.innerHTML = new BigNumber(input1.value).mul(input2.value)">求积</button>
<button onclick="output.innerHTML = new BigNumber(input1.value).div(input2.value)">求商</button>
<button onclick="output.innerHTML = new BigNumber(input1.value).pow(input2.value)">求幂</button>
<span id="output"></span>

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