답안 #22993

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
22993	2017-05-01T03:02:44 Z	model_code	Hacker (BOI15_hac)	C++11	20 / 100	1000 ms	1312 KB

hac

/*
    Task: Hacker
    Slow solution 2
    Author: Krzysztof Kiljan
    Complexity: O(n^3)

    Brutal simulation, for every start S we brutally calculate what would be the result
    if second player started in any of the remaining points. For every point, we also brutally
    calculate the sum of the points in it.
 */

#include<cstdio>
#include<cstdlib>
#include<algorithm>
#include<vector>

using namespace std;

#define REP(I,N) for(int I=0;I<(N);I++)
#define PB push_back
#define MP make_pair
#define ST first
#define ND second


typedef vector<int> VI;
typedef pair<int, int> PII;
typedef long long ll;

const int MAXN = 500013;
VI v;

int n, m, k, operCompNum, sumAll;

void readInput()
{
    sumAll = 0;
    scanf("%d", &n);

    operCompNum = n / 2;

    REP(i, n)
    {
        scanf("%d", &k);
        v.PB(k);
        sumAll += k;
    }
}

//makes   v -> vv, for easier further implementation

void duplicateV()
{
    REP(i, n)
    v.push_back(v[i]);
}


//Calculates the sum from computers protectected by operator if started at "start" position
int calcOperProtection(int start)
{
    int sum = 0;

    for (int i = start; i < start + operCompNum; i++)
        sum += v[i];

    return sum;
}

// Calculates the value hacker will get assuming he will start at computer number nr
// Numbers in <0, n)

int tryStart(int nr)
{
    int res = 0;

    for (int i = 1; i <= n - operCompNum; i++)
        res = max(res, calcOperProtection(i + nr));

    return sumAll - res;
}

int solve()
{
    int ans = 0;

    REP(i, n)
    ans = max(ans, tryStart(i));

    return ans;
}

int main()
{
    readInput();
    duplicateV();
    int ans = solve();
    printf("%d\n", ans);
    return 0;
}

Compilation message

hac.cpp: In function 'void readInput()':
hac.cpp:38:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &n);
                    ^
hac.cpp:44:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d", &k);
                        ^

Subtask #1

20.0 / 20.0

#	결과	실행 시간	메모리	Grader output
1	Correct	0 ms	1172 KB	Output is correct
2	Correct	0 ms	1172 KB	Output is correct
3	Correct	0 ms	1172 KB	Output is correct
4	Correct	0 ms	1172 KB	Output is correct
5	Correct	0 ms	1172 KB	Output is correct
6	Correct	0 ms	1172 KB	Output is correct
7	Correct	3 ms	1172 KB	Output is correct
8	Correct	3 ms	1172 KB	Output is correct
9	Correct	3 ms	1172 KB	Output is correct
10	Correct	3 ms	1172 KB	Output is correct
11	Correct	3 ms	1172 KB	Output is correct
12	Correct	3 ms	1172 KB	Output is correct
13	Correct	0 ms	1172 KB	Output is correct
14	Correct	0 ms	1172 KB	Output is correct
15	Correct	0 ms	1172 KB	Output is correct
16	Correct	3 ms	1172 KB	Output is correct
17	Correct	3 ms	1172 KB	Output is correct
18	Correct	3 ms	1172 KB	Output is correct

Subtask #2

0 / 20.0

#	결과	실행 시간	메모리	Grader output
1	Correct	0 ms	1172 KB	Output is correct
2	Correct	0 ms	1172 KB	Output is correct
3	Correct	0 ms	1172 KB	Output is correct
4	Correct	0 ms	1172 KB	Output is correct
5	Correct	0 ms	1172 KB	Output is correct
6	Correct	0 ms	1172 KB	Output is correct
7	Correct	3 ms	1172 KB	Output is correct
8	Correct	3 ms	1172 KB	Output is correct
9	Correct	3 ms	1172 KB	Output is correct
10	Correct	3 ms	1172 KB	Output is correct
11	Correct	3 ms	1172 KB	Output is correct
12	Correct	3 ms	1172 KB	Output is correct
13	Correct	0 ms	1172 KB	Output is correct
14	Correct	0 ms	1172 KB	Output is correct
15	Correct	0 ms	1172 KB	Output is correct
16	Correct	3 ms	1172 KB	Output is correct
17	Correct	3 ms	1172 KB	Output is correct
18	Correct	3 ms	1172 KB	Output is correct
19	Correct	16 ms	1172 KB	Output is correct
20	Correct	146 ms	1172 KB	Output is correct
21	Correct	63 ms	1172 KB	Output is correct
22	Execution timed out	1000 ms	1312 KB	Execution timed out
23	Halted	0 ms	0 KB	-

Subtask #3

0 / 20.0

#	결과	실행 시간	메모리	Grader output
1	Correct	0 ms	1172 KB	Output is correct
2	Correct	9 ms	1172 KB	Output is correct
3	Execution timed out	1000 ms	1312 KB	Execution timed out
4	Halted	0 ms	0 KB	-

Subtask #4

0 / 40.0

#	결과	실행 시간	메모리	Grader output
1	Correct	0 ms	1172 KB	Output is correct
2	Correct	0 ms	1172 KB	Output is correct
3	Correct	0 ms	1172 KB	Output is correct
4	Correct	0 ms	1172 KB	Output is correct
5	Correct	0 ms	1172 KB	Output is correct
6	Correct	0 ms	1172 KB	Output is correct
7	Correct	3 ms	1172 KB	Output is correct
8	Correct	3 ms	1172 KB	Output is correct
9	Correct	3 ms	1172 KB	Output is correct
10	Correct	3 ms	1172 KB	Output is correct
11	Correct	3 ms	1172 KB	Output is correct
12	Correct	3 ms	1172 KB	Output is correct
13	Correct	0 ms	1172 KB	Output is correct
14	Correct	0 ms	1172 KB	Output is correct
15	Correct	0 ms	1172 KB	Output is correct
16	Correct	3 ms	1172 KB	Output is correct
17	Correct	3 ms	1172 KB	Output is correct
18	Correct	3 ms	1172 KB	Output is correct
19	Correct	16 ms	1172 KB	Output is correct
20	Correct	146 ms	1172 KB	Output is correct
21	Correct	63 ms	1172 KB	Output is correct
22	Execution timed out	1000 ms	1312 KB	Execution timed out
23	Halted	0 ms	0 KB	-