【C++错误检查】binary '>>' :


f:\00数据结构编程\八排序\11.cpp(26) : error C2679:
binary '>>' : no operator defined which takes a right-hand operand of type 'class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >' (or there is no acceptable conver

sion)
f:\00数据结构编程\八排序\11.cpp(37) : error C2679: binary '<<' : no operator defined which takes a right-hand operand of type 'class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >' (or there is no
acceptable conver

sion)
错误原因：

              (1):没加#include <string>

              (2):程序中<<加了返回值为void类型的函数

<strong><span style="font-size:14px;">#include <iostream>
<span style="color:#ff0000;">//#include<string></span> //加了以后编译成功
#include <algorithm>
using namespace std;

typedef struct
{
string dna;
int count;
}DNA;
DNA dna[101];
int cmp(const void *a,const void *b)
{
DNA *aa = (DNA *)a;
DNA *bb = (DNA *)b;
return aa->count-bb->count;
}
int main()
{
int n,m;
char c;
cin>>n>>m;
int i;
for(i = 0; i < m; i++)
{
cin>>dna[i].dna;
dna[i].count = 0;
for(int j = 0; j < n; j++)
for(int k = j+1; k < n; k++)
{
if(dna[i].dna[j]>dna[i].dna[k])
dna[i].count++;
}
}
qsort(dna,m,sizeof(dna[0]),cmp);
for(i = 0; i < m; i++)
cout<<dna[i].dna<<endl;
return 0;
}</span></strong>