九度OJ 1551-1557（4/7）

1551

#include <stdio.h>
#include <stdlib.h>
#include <math.h>

#define PI (asin(1.0)*2)

int main(void)
{
 double R,r;
 while(scanf("%lf%lf",&R,&r)!=EOF)
 {
 if(r>1)
 r=1/r;
 double low=0,high=R;
 double s=PI*R*R*r/(1+r),l,result;
 while(1)
 {
 l=(low+high)/2;
 result=R*R*asin(l/R)-sqrt(R*R-l*l)*l;
 if(abs(result-s)<0.00001)
 break;
 if(result>s)
 high=l;
 if(result<s)
 low=l;
 }
 printf("%.2lf\n",2*l);
 }
 return 0;
}
/**************************************************************
 Problem: 1551
 User: liangrx06
 Language: C++
 Result: Wrong Answer
****************************************************************/

1552

#include <stdio.h>

#define N 1000
#define M 1000000007

int main()
{
 int i, n;
 int m[N], f[N];
 while(scanf("%d", &n) != EOF)
 {
 m[1] = 1;
 f[1] = 0;
 m[2] = f[2] = 1;
 for (i=3; i<=n; i++)
 {
 m[i] = (m[i-1] + f[i-1]) % M;
 f[i] = (f[i-1] + m[i-2]) % M;
 }
 printf("%d\n", (m[n]+f[n]) % M);
 }
 return 0;
}
/**************************************************************
 Problem: 1552
 User: liangrx06
 Language: C
 Result: Accepted
 Time:50 ms
 Memory:912 kb
****************************************************************/

1553

#include <stdio.h>

int main()
{
 double h, m;
 double res;
 while(scanf("%lf:%lf", &h, &m) != EOF)
 {
 h = (h+m/60)/12*360;
 m = m/60*360;
 res = h-m;
 if (res < 0)
 res = -res;
 if (res > 180)
 res = 360-res;
 printf("%.2lf\n", res);
 }
 return 0;
}
/**************************************************************
 Problem: 1553
 User: liangrx06
 Language: C
 Result: Accepted
 Time:0 ms
 Memory:912 kb
****************************************************************/

1554（未完成）

1555

//加上了释放动态内存函数del
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define N 1000

typedef struct node {
    char str[N+1];
    struct node *next;
} Str;

int search(Str *sub, char s[])
{
    while (sub) {
        if (strcmp(sub->str, s) == 0) return 1;
        sub = sub->next;
    }
    return 0;
}

Str *insert(Str *sub, char s[])
{
    Str *p = (Str *)malloc(sizeof(Str));
    strcpy(p->str, s);
    p->next = sub;
    return p;
}

void del(Str *sub)
{   
    Str *p;
    while (sub) {
        p = sub->next;
        free(sub);
        sub = p;
    }
}

int main()
{
    int i, j, n;
    char s[N+1], s1[N+1];
    Str *sub[N/2+1];
    int count;

    while(scanf("%s", s) != EOF)
    {
        count = 0;
        memset(sub, 0, sizeof(sub));
        n = strlen(s);
        for (i=0; i<n; i++)
        {
            for (j=1; j<=(n-i)/2; j++)
            {
                strncpy(s1, s+i, j);
                s1[j] = '\0';
                if (strstr(s+i+j, s1))
                {
                    if (search(sub[j], s1) == 0) {
                        count ++;
                        sub[j] = insert(sub[j], s1);
                    }
                }
                else
                    break;
            }
        }
        for (i=1; i<=n/2; i++)
            del(sub[i]);
        printf("%d\n", count);
    }
    return 0;
}
/**************************************************************
    Problem: 1555
    User: liangrx06
    Language: C
    Result: Accepted
    Time:90 ms
    Memory:1180 kb
****************************************************************/

1556-1557（未完成）