以下片段输出0.29847,当我预期0.29848时:
double f = 0.298475;
cout << setprecision(5) << f << endl;
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但是,对于其他例子,我观察四舍五入:
double f = 0.123459;
cout << setprecision(5) << f << endl;
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输出:0.12346
和
double f = 0.123454;
cout << setprecision(5) << f << endl;
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输出:0.12345