zoj 1828 Fibonacci Numbers

A Fibonacci sequence is calculated by adding the previous two members of the sequence, with the first two members being both 1.

f(1) = 1, f(2) = 1, f(n > 2) = f(n - 1) + f(n - 2)

Your task is to take a number as input, and print that Fibonacci number.

Sample Input

100

Sample Output

354224848179261915075

Note:

No generated Fibonacci number in excess of 1000 digits will be in the test data, i.e. f(20) = 6765 has 4 digits.

注意有多个测试样例。

代码：

#include <iostream>
#include <cstdio>
#include <vector>
#include <cstdlib>
#include <cstring>
#include <algorithm>
#define inf 0x3f3f3f3f
using namespace std;

int n;

int main() {
    while(~scanf("%d",&n)) {
        char s[][] = {"",""};
        char *a = s[],*b = s[];
        for(int i = ;i <= n;i ++) {
            int d = ,j;
            for(j = ;a[j];j ++) {
                if(b[j]) d += b[j] - '';
                d += a[j] - '';
                b[j] = d %  + '';
                d /= ;
            }
            while(d) {
                b[j ++] = d %  + '';
                d /= ;
            }
            b[j] = ;
            swap(a,b);
        }
        reverse(a,a + strlen(a));
        printf("%s\n",a);
    }
}