Codeforces Round #493 (Div. 2) B. Cutting 前缀和优化_动归水题
不解释,题目过水
Code:
#include<cstdio>
#include<cmath>
#include<algorithm>
using namespace std;
const int maxn = 1000 + 3;
int A[maxn], n, odds[maxn], f[200][200],b;
int main()
{
scanf("%d%d",&n,&b);
for(int i = 1;i <= n; ++i)
{
scanf("%d",&A[i]);
if(A[i] % 2 == 1) odds[i] = 1;
odds[i] += odds[i - 1];
}
for(int i = 1;i <= n; ++i)
{
for(int k = 0;k <= b; ++k)
{
for(int j = 1;j < i; ++j)
{
int delta = abs(A[j] - A[j + 1]);
if((odds[i] - odds[j]) * 2 != i - j) continue;
if(k - delta >= 0) f[i][k] = max(f[i][k], f[j][k - delta] + 1);
}
}
}
printf("%d",f[n][b]);
return 0;
}