32 lines
1022 B
Java
32 lines
1022 B
Java
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package Course_Codes;
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import java.math.BigDecimal;
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public class <EFBFBD><EFBFBD><EFBFBD><EFBFBD>PIС<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>nλ {
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public static void main(String[] args) {
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int n=1000;
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PI(n);
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}
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public static void PI(int n) {
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BigDecimal qian=BigDecimal.ZERO;//ǰ<>벿<EFBFBD><EBB2BF>
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BigDecimal hou=BigDecimal.ZERO;//<2F><><EFBFBD>벿<EFBFBD><EBB2BF>
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BigDecimal ans=BigDecimal.ZERO;//<2F><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>pi
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int jd=1000;//<2F><>ȷ<EFBFBD><C8B7>С<EFBFBD><D0A1><EFBFBD><EFBFBD><EFBFBD><EFBFBD>1000λ
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for(int i=0;i<n;i++) {
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BigDecimal de5=new BigDecimal("1").divide(new BigDecimal(2*i+1+"")
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.multiply(new BigDecimal("5").pow(2*i+1)),jd,BigDecimal.ROUND_DOWN);
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BigDecimal de239=new BigDecimal("1").divide(new BigDecimal(2*i+1+"")
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.multiply(new BigDecimal("239").pow(2*i+1)),jd,BigDecimal.ROUND_DOWN);
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BigDecimal fh=new BigDecimal((i%2==0?1:-1)+"");//<2F>ж<EFBFBD><D0B6><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
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qian=qian.add(de5.multiply(fh));
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hou=hou.add(de239.multiply(fh));
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}
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ans=new BigDecimal("16").multiply(qian).subtract(new BigDecimal("4").multiply(hou));
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System.out.println(ans.toString());
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}
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}
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