P1164-小A点菜 

 1 #include <bits/stdc++.h>
 2 #define _for(i,a,b) for(int i = (a);i < b;i ++)
 3 typedef long long ll;
 4 using namespace std;
 5 inline ll read()
 6 {
 7     ll ans = 0;
 8     char ch = getchar(), last = ' ';
 9     while(!isdigit(ch)) last = ch, ch = getchar();
10     while(isdigit(ch)) ans = (ans << 1) + (ans << 3) + ch - '0', ch = getchar();
11     if(last == '-') ans = -ans;
12     return ans;
13 }
14 inline void write(ll x)
15 {
16     if(x < 0) x = -x, putchar('-');
17     if(x >= 10) write(x / 10);
18     putchar(x % 10 + '0');
19 }
20 int N,M;
21 int a[101];
22 int dp[10003];
23 int main()
24 {
25     N = read(),M = read();
26     _for(i,0,N)
27         a[i] = read();
28     memset(dp,0,sizeof(dp));
29     dp[0] = 1;
30     _for(i,0,N)
31         for(int j = M;j >= 0;j --)
32             if(j>=a[i])
33                 dp[j] += dp[j-a[i]];
34     write(dp[3]);
35     return 0;
36 }

 

posted @ 2019-08-05 14:44  Asurudo  阅读(120)  评论(0)    收藏  举报