看你题干的意思应该不是一起输入50个,而是一个一个输入用-1作为结束输入,下面是C++代码:
#include <iostream>
using namespace std;
void main()
{
//int arr[50] = {5};
int i = 0;
int a = 0;
int count[5] = {0};
int num = 0;
cout << "从键盘输入50个整数,其值在0~4的范围内,用-1作为输入结束的标志。" << endl;
while (1)
{
cin >> a;
if (a == -1 || num == 50)
{
break;
}
else if (a<0 || a>4)
{
cout << "输入有误" << endl;
}
else
{
switch (a)
{
case 0:
count[0]++;
break;
case 1:
count[1]++;
break;
case 2:
count[2]++;
break;
case 3:
count[3]++;
break;
case 4:
count[4]++;
break;
}
num++;
}
}
for (i=0; i<5; i++)
{
cout << "输入" << i << "的次数是:" << count[i] << endl;
}
}