c语言代码解决问题

解题思路:

注意事项:

参考代码:

#include<stdio.h>

#include<string.h>

int main()

{

    int k;

    scanf("%d", &k);

    char str[1001];

    scanf("%s", str);

    int len = strlen(str),i,sum=1,flag=0;

    for (i = 0; i < len-1; i++)

    {

        if (str[i] == str[i + 1])

            sum++;

        else

            sum = 1;

        if (sum == k)

        {

            printf("%c", str[i]);

            flag = 1;

            break;

        }

    }

    if (flag == 0)

        printf("No");

    return 0;

}