这样都错了，求解答解决方法

  const int NUM=26;
  int counts[NUM]={0};
  char letters{NUM};//楼主你这儿错了，应该是[]

------解决方案--------------------
数组越界 比如counts[i]++; 这个i可能大于26 也可能小于0

------解决方案--------------------
修改后的：
#include<iostream>
using namespace std;
int main()
{
	const int N=80;
	char buffer[N];
	int k=0;
	const int NUM=26;
	int counts[NUM]={0};
	char letters[NUM] = {0};
	int i=0;
	do
	{
	cout<<"Enter a string:"<<endl;
	cin.getline(buffer, N, '\n');
	k=0;

	while(buffer[k] != 0)
	{
		i = tolower(buffer[k])-'a';
		counts[i] += 1;
		k++;
	}
		}while(buffer[0]!=0);
	cout<<"The statistic result is:"<<endl;
	for(i=0;i<NUM;i++)
	{
		letters[i]=(char)('a'+i); //1)
		if(counts[i]>0)
		{
			cout<<letters[i]<<":"<<counts[i]<<endl; //2)

		}
	}
	return 0;
}

------解决方案--------------------

C/C++ code

while(buffer[k]!='\n')
        {
            i=tolower(buffer[k]-'a');
            counts[i]++;
            k++;
        }

------解决方案--------------------
#include<iostream>
using namespace std;
int main()
{
 const int N=80;
 char buffer[N];
 int k=0;
 const int NUM=26;
 int counts[NUM]={0};
 char letters[NUM];
 int i=0;
 do
 {
 cout<<"Enter a string:"<<endl;
 cin.getline(buffer,N,'\n');
 k=0;
 while(buffer[k]!='\n')
 {
 i=tolower(buffer[k]-'a');
 counts[i]++;
 k++;
 }
 }while(buffer[0]!='\n');
 cout<<"The statistic result is:"<<endl;
 for(i=0;i<NUM;i++)
 {
 letters[i]=(char)('a'+i); //1)
 if(counts[i]>0)
 {
 cout<<letters[i]<<":"<<counts[i]<<endl; //2)

 }
 }
 return 0;
}