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Codeforces Round #493 (Div. 2) B. Cutting 字首和優化_動歸水題

不解釋,題目過水 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; }