CodeChef A

问题是求出斐波那契数列的第n个，这里要用大数加法预处理，然后就可以了

代码：

#include <iostream>
#include <sstream>
#include <cstdio>
#include <climits>
#include <cstring>
#include <cstdlib>
#include <string>
#include <stack>
#include <map>
#include <cmath>
#include <vector>
#include <queue>
#include <algorithm>
#define esp 1e-6
#define pi acos(-1.0)
#define pb push_back
#define lson l, m, rt<<1
#define rson m+1, r, rt<<1|1
#define mp(a, b) make_pair((a), (b))
#define in  freopen("in.txt", "r", stdin);
#define out freopen("out.txt", "w", stdout);
#define print(a) printf("%d
",(a));
#define bug puts("********))))))");
#define stop  system("pause");
#define Rep(i, c) for(__typeof(c.end()) i = c.begin(); i != c.end(); i++)
#define inf 0x0f0f0f0f

using namespace std;
typedef long long  LL;
typedef vector<int> VI;
typedef pair<int, int> pii;
typedef vector<pii> VII;
typedef vector<pii, int> VIII;
typedef VI:: iterator IT;
struct BigInt
{
    int len;
    int f[1100];
    void Init(int n)
    {
        memset(f, 0, sizeof(f));
        len = 0;
        while(n)
        {
            f[len] = n % 10;
            n /= 10;
            len++;
        }

        if(len > 0)
        len--;
    }
    BigInt operator + (const BigInt &a)const
    {
        int carry = 0;
        BigInt c;
        c.Init(0);
       int i;
        for(i = 0; i <= max(a.len, len); i++)
        {
            carry = carry + f[i] + a.f[i];
            c.f[i] = carry%10;
            carry /= 10;
        }
        if(carry == 0)
            return         c.len = i - 1, c;
        while(carry)
        {
            c.f[i] = carry%10;
            carry /= 10;
            i++;
        }
        c.len = i-1;
        return c;
    }
};

BigInt fi[11000];
int main(void)
{
    fi[1].Init(1);
    fi[2].Init(1);
    for(int i = 3; i <= 2000; i++)
        fi[i] = fi[i-2] + fi[i-1];
    int t;
    while(scanf("%d", &t), t)
    {
        for(int i = fi[t].len; i >= 0; i--)
            printf("%d", fi[t].f[i]);
        puts("");
    }
    return 0;
}