Submission #157316

#	Time	Username	Problem	Language	Result	Execution time	Memory
157316		karma	스트랩 (JOI14_straps)	C++14	45 / 100	51 ms	31868 KiB

straps

#include<bits/stdc++.h>
#define FileName      "test"
#define ll            long long
#define pb            emplace_back
#define deg           first
#define c             second

using namespace std;

typedef pair<int, int> pii;
const int N = int(4e3) + 2;
const int oo = int(2e9) + 7;

int f[N][N], Max[N], a[N];
int n, m, res = 0, pre;
pii val[N];

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    if(fopen(FileName".inp", "r")) {
       freopen(FileName".inp", "r", stdin);
       freopen(FileName".out", "w", stdout);
    }

    cin >> n; m = 2 * n;
    for(int i = 1; i <= n; ++i) {
        cin >> val[i].deg >> val[i].c;
        fill(f[i], f[i] + m + 1, -oo);
    }
    sort(val + 1, val + n + 1, [](const pii& x, const pii& y) {
             return x.deg > y.deg;
         });
    /// f(i, j) = max niem vui khi den cai thu i va co j cong ket noi
    fill(Max, Max + m + 1, -oo);
    f[0][1] = 0; Max[1] = 0;
    for(int i = 1; i <= n; ++i) {
       for(int j = 0; j <= m; ++j) {
          pre = min(j + 1 - val[i].deg, m);
          if(pre < 0 || Max[pre] == -oo) continue;
          res = max(res, (f[i][j] = Max[pre] + val[i].c));
       }
       for(int j = 0; j <= m; ++j) Max[j] = max(Max[j], f[i][j]);
    }
    cout << res;
}

Compilation message (stderr)

straps.cpp: In function 'int main()':
straps.cpp:23:15: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
        freopen(FileName".inp", "r", stdin);
        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
straps.cpp:24:15: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
        freopen(FileName".out", "w", stdout);
        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 5
• Subtask 2: 0 / 5
• Subtask 3: 45 / 45
• Subtask 4: 0 / 45