UVa 11375 Matches:DP&高精度2014-10-02 csdn博客 synapse7
11375 - Matches
Time limit: 2.000 secondsWe can make digits with matches as shown below:

Given N matches, find the number of different numbers representable using the matches. We shall only make numbers greater than or equal to 0, so no negative signs should be used. For instance, if you have 3 matches, then you can only make the numbers 1 or 7. If you have 4 matches, then you can make the numbers 1, 4, 7 or 11. Note that leading zeros are not allowed (e.g. 001, 042, etc. are illegal). Numbers such as 0, 20, 101 etc. are permitted, though.InputInput contains no more than 100 lines. Each line contains one integer N (1 ≤ N ≤ 2000).
Output
For each N, output the number of different (non-negative) numbers representable if you have N matches.
Sample Input
34
Sample Output
24
简单DP。完整代码:
/*0.076s*/#include<cstdio>#include<cstring>#include<algorithm>using namespace std;const int maxn = 2001;// 本文URL地址:http://www.bianceng.cn/Programming/sjjg/201410/45373.htmconst int c[] = {6, 2, 5, 5, 4, 5, 6, 3, 7, 6}; ///c[i]表示数字i需要的火柴数struct node{int p[500], len;node(){memset(p, 0, sizeof(p));len = 0;}node(int a){p[0] = a;len = 1;}node operator + (const node& a) const{node b;b.len = max(len, a.len);for (int i = 0; i < b.len; i++){b.p[i] += p[i] + a.p[i];b.p[i + 1] = b.p[i] / 10;b.p[i] %= 10;}if (b.p[b.len] > 0) b.len++;return b;}node operator += (const node& a){*this = *this + a;return *this;}void out(){if (len == 0) putchar("0");else{for (int i = len - 1; i >= 0; i--)printf("%d", p[i]);}putchar(10);}} d[maxn];int main(){int i, j, n;d[0] = node(1);for (i = 0; i < maxn; ++i)for (j = 0; j < 10; ++j)if (i + c[j] < maxn && (i || j))d[i + c[j]] += d[i];d[6] += node(1);for (i = 2; i < maxn; ++i) d[i] += d[i - 1];while (~scanf("%d", &n))d[n].out();return 0;}