uva10183-多少个Fib

Posted 2020-08-09 啊嘞

题目链接 http://vjudge.net/problem/21247

 

题意 给A,B。求[A, B] 内有多少个fib数。

 

解题思路

　　直接高精度模拟

 

代码

#include<stdio.h>
#include<string.h>
#define MAX_SIZE 110
#define MAX_LEN 1010
char a[MAX_SIZE], b[MAX_SIZE];
int f[MAX_LEN][MAX_SIZE];
int len[MAX_LEN];
int cmp(int *x, char *y, int m)
{
    int i = 0;
    if(m < strlen(y)) return -1;
    if(m > strlen(y)) return 1;
    while(i < m && x[MAX_SIZE-m+i] == y[i] - ‘0‘) i++;
    if(i == m) return 0;
    return x[MAX_SIZE-m+i] - y[i] + ‘0‘;
}
void add(int *res, int *x, int *y, int lenx, int leny, int index)
{
    int m = lenx > leny ? lenx : leny;
    int i = 1;
    int k = 0;
    len[index] = m;
    while(i <= m) {
        res[MAX_SIZE-i] = x[MAX_SIZE-i] + y[MAX_SIZE-i] + k;
        k = res[MAX_SIZE-i] / 10;
        res[MAX_SIZE-i] %= 10;
        i++;
    }
    if(k != 0) { res[MAX_SIZE-i] = k; len[index]++; }
}
int main()
{
    scanf("%s%s", a, b);
    while(!(a[0] == ‘0‘ && b[0] == ‘0‘)) {
        f[1][MAX_SIZE-1] = 1; len[1] = 1;
        f[2][MAX_SIZE-1] = 2; len[2] = 1;
        int i = 1;
        int count = 0;
        do {
            if(cmp(f[i], a, len[i]) >= 0) count++;
            i++;
            if(i >= 3) add(f[i], f[i-1], f[i-2], len[i-1], len[i-2], i);
        }while(cmp(f[i], b, len[i]) <= 0);
        printf("%d\n", count);
        scanf("%s%s", a, b);
    }
    return 0;
}