这是一个 toString 方法，用于格式化多项式的项并将它们添加到字符串中。它的最终输出类似于“+ 2x^2 + 2x + 1” 我将如何删除第一个加号？谢谢
//toString method for returning ReesePolynomials in polynomaial format(for ReeseClient)
public String toString()
{
String output = "";
//the following are situations for formatting the output of each term and adding them to String output
for (int i = 0; i < TermLength; i++) // For the number of terms stated by the user earlier, values will be given for each ReeseTerm in the poly array
{
if (poly[i].getExpo() == 0 && poly[i].getCoeff() > 0)
{
output += " + " + poly[i].getCoeff();
}
else if (poly[i].getExpo() == 0 && poly[i].getCoeff() < 0)
{
output += " " + poly[i].getCoeff();
}
else if (poly[i].getCoeff() == 1 && (poly[i].getExpo() != 0 && poly[i].getExpo() != 1))
{
output += " + x^" + poly[i].getExpo();
}
else if (poly[i].getCoeff() == 1 && (poly[i].getExpo() == 1))
{
output += " + x";
}
else if (poly[i].getExpo() == 1 && poly[i].getCoeff() > 0)
{
output += " + " + poly[i].getCoeff() + "x";
}
else if (poly[i].getExpo() == 1 && poly[i].getCoeff() < 0)
{
output += " " + poly[i].getCoeff() + "x";
}
else if (poly[i].getCoeff() < 0 && (poly[i].getExpo() > 1 || poly[i].getExpo() < -1))
{
output += " " + poly[i].getCoeff() + "x^" + poly[i].getExpo();
}
else if (poly[i].getCoeff() == 0)
{}
else
{
output += " + " + poly[i].getCoeff() + "x^" + poly[i].getExpo();
}
}
return output; // the final string output is returned to be printed when called upon in main
}
最佳答案
在 return 语句之前，使用 substring 方法:
output = output.substring(2);
这将为您提供从索引 2 到末尾的所有字符。 http://docs.oracle.com/javase/7/docs/api/java/lang/String.html
您面临的问题通常称为栅栏问题，或差一错误。 http://en.wikipedia.org/wiki/Off-by-one_error
关于java - 多项式的 toString 方法，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/20227265/