Submission #198705

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
198705	2020-01-27T12:35:44 Z	SamAnd	Mecho (IOI09_mecho)	C++17	100 / 100	388 ms	8420 KB

mecho

#include <bits/stdc++.h>
using namespace std;
const int N = 802;
const int xx[4] = {0, 1, 0, -1};
const int yy[4] = {1, 0, -1, 0};
struct ban
{
    int x, y;
    ban(){}
    ban(int x, int y)
    {
        this->x = x;
        this->y = y;
    }
};

int n, s;
int mx, my;
vector<ban> hh;
char a[N][N];

bool ch[N][N];
int dh[N][N];
bool cm[N][N];
int dm[N][N];

bool stg(int x)
{
    memset(ch, false, sizeof ch);
    memset(cm, false, sizeof cm);
    queue<ban> qh;
    queue<ban> qm;
    for (int i = 0; i < hh.size(); ++i)
    {
        ch[hh[i].x][hh[i].y] = true;
        qh.push(hh[i]);
    }
    while (!qh.empty())
    {
        ban t = qh.front();
        if (dh[t.x][t.y] == x)
            break;
        qh.pop();
        for (int i = 0; i < 4; ++i)
        {
            ban h = t;
            h.x += xx[i];
            h.y += yy[i];
            if (h.x >= 0 && h.x < n && h.y >= 0 && h.y < n)
            {
                if (a[h.x][h.y] == 'G' && !ch[h.x][h.y])
                {
                    ch[h.x][h.y] = true;
                    dh[h.x][h.y] = dh[t.x][t.y] + 1;
                    qh.push(h);
                }
            }
        }
    }
    qm.push(ban(mx, my));
    cm[mx][my] = true;
    for (int ii = 0; ; ++ii)
    {
        if (qm.empty())
            return false;
        while (!qm.empty())
        {
            ban t = qm.front();
            if (dm[t.x][t.y] == (ii + 1) * s)
                break;
            qm.pop();
            if (ch[t.x][t.y])
                continue;
            if (a[t.x][t.y] == 'D')
                return true;
            for (int i = 0; i < 4; ++i)
            {
                ban h = t;
                h.x += xx[i];
                h.y += yy[i];
                if (h.x >= 0 && h.x < n && h.y >= 0 && h.y < n)
                {
                    if ((a[h.x][h.y] == 'G' || a[h.x][h.y] == 'D') && !cm[h.x][h.y] && !ch[h.x][h.y])
                    {
                        cm[h.x][h.y] = true;
                        dm[h.x][h.y] = dm[t.x][t.y] + 1;
                        qm.push(h);
                    }
                }
            }
        }
        while (!qh.empty())
        {
            ban t = qh.front();
            if (dh[t.x][t.y] == x + ii + 1)
                break;
            qh.pop();
            for (int i = 0; i < 4; ++i)
            {
                ban h = t;
                h.x += xx[i];
                h.y += yy[i];
                if (h.x >= 0 && h.x < n && h.y >= 0 && h.y < n)
                {
                    if (a[h.x][h.y] == 'G' && !ch[h.x][h.y])
                    {
                        ch[h.x][h.y] = true;
                        dh[h.x][h.y] = dh[t.x][t.y] + 1;
                        qh.push(h);
                    }
                }
            }
        }
    }
}

int main()
{
    //freopen("input.txt", "r", stdin);
    scanf("%d%d", &n, &s);
    for (int i = 0; i < n; ++i)
    {
        scanf(" %s", a[i]);
        for (int j = 0; j < n; ++j)
        {
            if (a[i][j] == 'M')
            {
                mx = i;
                my = j;
                a[i][j] = 'G';
            }
            if (a[i][j] == 'H')
            {
                hh.push_back(ban(i, j));
                a[i][j] = 'G';
            }
        }
    }
    int l = 0, r = n * n;
    int ans = -1;
    while (l <= r)
    {
        int m = (l + r) / 2;
        if (stg(m))
        {
            ans = m;
            l = m + 1;
        }
        else
            r = m - 1;
    }
    printf("%d\n", ans);
    return 0;
}

Compilation message

mecho.cpp: In function 'bool stg(int)':
mecho.cpp:33:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int i = 0; i < hh.size(); ++i)
                     ~~^~~~~~~~~~~
mecho.cpp: In function 'int main()':
mecho.cpp:120:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d", &n, &s);
     ~~~~~^~~~~~~~~~~~~~~~
mecho.cpp:123:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf(" %s", a[i]);
         ~~~~~^~~~~~~~~~~~~

Subtask #1

100.0 / 100.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	6 ms	1656 KB	Output is correct
2	Correct	6 ms	1656 KB	Output is correct
3	Correct	7 ms	1656 KB	Output is correct
4	Correct	6 ms	1656 KB	Output is correct
5	Correct	6 ms	1656 KB	Output is correct
6	Correct	6 ms	1656 KB	Output is correct
7	Correct	316 ms	7032 KB	Output is correct
8	Correct	6 ms	1656 KB	Output is correct
9	Correct	6 ms	1656 KB	Output is correct
10	Correct	7 ms	1656 KB	Output is correct
11	Correct	6 ms	1660 KB	Output is correct
12	Correct	7 ms	1784 KB	Output is correct
13	Correct	9 ms	1784 KB	Output is correct
14	Correct	8 ms	1912 KB	Output is correct
15	Correct	6 ms	1656 KB	Output is correct
16	Correct	7 ms	1656 KB	Output is correct
17	Correct	7 ms	1656 KB	Output is correct
18	Correct	7 ms	1784 KB	Output is correct
19	Correct	7 ms	1784 KB	Output is correct
20	Correct	6 ms	1784 KB	Output is correct
21	Correct	7 ms	1784 KB	Output is correct
22	Correct	7 ms	1784 KB	Output is correct
23	Correct	7 ms	1784 KB	Output is correct
24	Correct	7 ms	1788 KB	Output is correct
25	Correct	7 ms	1784 KB	Output is correct
26	Correct	7 ms	1784 KB	Output is correct
27	Correct	7 ms	1888 KB	Output is correct
28	Correct	8 ms	1912 KB	Output is correct
29	Correct	7 ms	1916 KB	Output is correct
30	Correct	7 ms	1912 KB	Output is correct
31	Correct	8 ms	1912 KB	Output is correct
32	Correct	8 ms	1912 KB	Output is correct
33	Correct	32 ms	3064 KB	Output is correct
34	Correct	29 ms	3064 KB	Output is correct
35	Correct	40 ms	4216 KB	Output is correct
36	Correct	36 ms	3320 KB	Output is correct
37	Correct	36 ms	3320 KB	Output is correct
38	Correct	51 ms	4600 KB	Output is correct
39	Correct	56 ms	3576 KB	Output is correct
40	Correct	42 ms	3576 KB	Output is correct
41	Correct	69 ms	4984 KB	Output is correct
42	Correct	54 ms	3832 KB	Output is correct
43	Correct	50 ms	3832 KB	Output is correct
44	Correct	88 ms	5368 KB	Output is correct
45	Correct	67 ms	4216 KB	Output is correct
46	Correct	56 ms	4088 KB	Output is correct
47	Correct	91 ms	5752 KB	Output is correct
48	Correct	72 ms	4344 KB	Output is correct
49	Correct	68 ms	4376 KB	Output is correct
50	Correct	124 ms	6264 KB	Output is correct
51	Correct	95 ms	4728 KB	Output is correct
52	Correct	83 ms	4600 KB	Output is correct
53	Correct	137 ms	6648 KB	Output is correct
54	Correct	106 ms	4856 KB	Output is correct
55	Correct	99 ms	4856 KB	Output is correct
56	Correct	182 ms	7032 KB	Output is correct
57	Correct	116 ms	5112 KB	Output is correct
58	Correct	108 ms	5184 KB	Output is correct
59	Correct	205 ms	7544 KB	Output is correct
60	Correct	142 ms	5368 KB	Output is correct
61	Correct	121 ms	5368 KB	Output is correct
62	Correct	230 ms	8056 KB	Output is correct
63	Correct	336 ms	7928 KB	Output is correct
64	Correct	341 ms	7928 KB	Output is correct
65	Correct	307 ms	7928 KB	Output is correct
66	Correct	346 ms	7928 KB	Output is correct
67	Correct	333 ms	7928 KB	Output is correct
68	Correct	341 ms	7928 KB	Output is correct
69	Correct	303 ms	8056 KB	Output is correct
70	Correct	317 ms	8004 KB	Output is correct
71	Correct	375 ms	8060 KB	Output is correct
72	Correct	388 ms	6008 KB	Output is correct
73	Correct	271 ms	8212 KB	Output is correct
74	Correct	347 ms	8128 KB	Output is correct
75	Correct	380 ms	8336 KB	Output is correct
76	Correct	360 ms	8200 KB	Output is correct
77	Correct	370 ms	8420 KB	Output is correct
78	Correct	326 ms	7004 KB	Output is correct
79	Correct	322 ms	6792 KB	Output is correct
80	Correct	338 ms	6624 KB	Output is correct
81	Correct	330 ms	6732 KB	Output is correct
82	Correct	326 ms	6732 KB	Output is correct
83	Correct	333 ms	7132 KB	Output is correct
84	Correct	333 ms	6984 KB	Output is correct
85	Correct	345 ms	6836 KB	Output is correct
86	Correct	345 ms	6992 KB	Output is correct
87	Correct	331 ms	7048 KB	Output is correct
88	Correct	320 ms	7064 KB	Output is correct
89	Correct	315 ms	6940 KB	Output is correct
90	Correct	323 ms	7068 KB	Output is correct
91	Correct	327 ms	6988 KB	Output is correct
92	Correct	336 ms	6968 KB	Output is correct