按与给定字符ASCII值的差的绝对值 字符排序

#include<iostream>
#include<string>
using namespace std;

void main()
{
	string str;
	cin>>str;

	int length = str.length();
	int a[100]={0};
	char str_to[100]={'\0'};

	//计算与字符'U'差的绝对值
	for(int i=0;i<length;i++)
	{
		a[i]=abs(str[i]-'U');
		str_to[i] = str[i];
	}
	cout<<str_to<<endl;

	for( i=0;i<length;i++)
	{
		cout<<a[i]<<',';
	}
	cout<<endl;
	//对绝对值排序，为0的不参与排序，即原来为字符'U'
	int temp=1000;
	int k=0;

	//选择排序法
	for( i=0;i<length;i++)
	{
		temp=1000;
		//为0的不参与排序
		if(a[i]==0)	continue;
		else
		{
			k = i ;
			for(int j=i;j<length;j++)
			{//为0的不参与排序
				if(a[j]==0)
					continue;
				//找到此次循环中最小的值
				if(a[j]<temp)
				{
					k = j ;
					temp = a[j] ;
				}
			}
			//交换对应字符串的字符
			if(k!=i)
			{
				int tt = a[i];
				a[i] = a[k] ;
				a[k] = tt;

				char c = str_to[i];
				str_to[i] = str_to[k];
				str_to[k] = c ;
			}
		}
	}
	str_to[length]='\0';

	for( i=0;i<length;i++)
	{
		cout<<a[i]<<',';
	}
	cout<<endl;

	cout<<"排序处理后的字符串：";
	cout<<str_to<<endl;
	getchar();
}