这是一个toString方法，用于格式化多项式的项并将其添加到String中。它的最终输出是“ + 2x ^ 2 + 2x +1”之类的东西。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到结尾的所有字符。
http://docs.oracle.com/javase/7/docs/api/java/lang/String.html
您面临的问题通常称为击剑岗问题，或一站式错误。
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/