PAT部分样例通过，但是我感觉我的代码没问题

我想知道还有哪些样例不能通过

我的代码可以不在同一天，我搞不懂为啥不能通过所有样例

#include
int main()
{
    int a,b,c,h,m;
    scanf("%d %d",&a,&b);
    h = a/100+b/60;
    m = a%100+b%60;
    if(m<60)
    {
        if(h<24&&h>0)
        {
            c = 100*h+m;
            /*if (c<1000)
            printf("0%d",c);
            else*/
            printf("%d",c);
        }
        else if("h == 0")
        {
            if(m<0)
            {
                h = 23+h;
                m = m+60;
                c = 100*h+m;
                printf("%d",c);
            }
            else
            {
                h = 23+h;
                m = m+60;
                c = 100*h+m;
                if(m>=10&&m<60)
                printf("0%d",m);
                else if(m>=60)
                {
                    m = m-60;
                    if (m>=10)
                    printf("0%d",m);
                    else
                    printf("00%d",m);
                }
                else
                printf("0%d",m);
            }
        }
        else if(h>24)
        {
            h = h-24;
            c = 100*a+b;
            printf("%d",c);
        }
        else
        {
            h = h+24;
            c = 100*a+b;
            printf("%d",c);
        }
    }
    else
    {
        h = h+1;
        m = m-60;
        if(h<24&&h>0)
        {
            if (h<10)
            {
            c = 100*h+m;
            printf("%d",c);    
            }
            else
            {
                c = 100*h+m;
            printf("%d",c);
            }
        }
        else if("h == 0")
        {
            printf("0%d",m);
        }
        else if(h>24)
        {
            h = h-24;
            c = 100*a+b;
            printf("%d",c);
        }
        else
        {
            h = h+24;
            c = 100*a+b;
            printf("%d",c);
        }
    }
    return 0;
}

请帮忙解答，谢谢