/**
https://boi2013.informatik-olympiade.de/wp-content/uploads/2013/05/tracks-spoiler.pdf
*/
/**
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*/
#include <cstring>
#include <vector>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <queue>
#include <cmath>
#include <cstdlib>
#include <ctime>
#include <cassert>
#pragma GCC optimize("Ofast")
#define F first
#define S second
#define endl '\n'
#define deb(x) cout<<#x<<' '<<x<<endl;
#define pb push_back
/*
#ifdef IZI_KATKA
#define int __int64_t
#else
#define int __int64
#endif
*/
const long long MOD = 1e9 + 7;
const long long MAXN = 1e6 + 1;
using namespace std;
typedef long long ll;
long long readInt() {
bool minus1 = false;
long long result = 0;
char ch;
ch = getchar();
while (true) {
if (ch == '-') break;
if (ch >= '0' && ch <= '9') break;
ch = getchar();
}
if (ch == '-') minus1 = true; else result = ch-'0';
while (true) {
ch = getchar();
if (ch < '0' || ch > '9') break;
result = result*10 + (ch - '0');
}
if (minus1)
return -result;
else
return result;
}
/************************************************************************************************/
static struct IO {char tmp[1 << 10];char cur;inline char nextChar()
{ return cur = getc_unlocked(stdin); }inline char peekChar() { return cur; }
inline operator bool() { return peekChar(); }inline static bool isBlank(char c)
{ return (c < '-' && c); }inline bool skipBlanks()
{ while (isBlank(nextChar())); return peekChar() != 0; }
inline IO& operator >> (char & c) { c = nextChar(); return *this; }
inline IO& operator >> (char * buf) {if (skipBlanks()) {if (peekChar()) {*(buf++) = peekChar();
while (!isBlank(nextChar())) *(buf++) = peekChar();} *(buf++) = 0; } return *this; }
inline IO& operator >> (string & s) {if (skipBlanks()) { s.clear(); s += peekChar();
while (!isBlank(nextChar())) s += peekChar(); }return *this; }
inline IO& operator >> (double & d) { if ((*this) >> tmp) sscanf(tmp, "%lf", &d); return *this; }
#define defineInFor(intType) inline IO& operator >>(intType & n) { if (skipBlanks()) { \
int sign = +1; if (peekChar() == '-') { sign = -1; n = nextChar() - '0'; } else \
n = peekChar() - '0'; while (!isBlank(nextChar())) { n += n + (n << 3) + peekChar() - 48; } \
n *= sign; } return *this; }
defineInFor(int)defineInFor(unsigned int)defineInFor(long long)
inline void putChar(char c) { putc_unlocked(c, stdout); }inline IO& operator << (char c) { putChar(c); return *this; }
inline IO& operator << (const char * s) { while (*s) putChar(*s++); return *this; }
inline IO& operator << (const string & s) { for (int i = 0; i < (int)s.size(); ++i) putChar(s[i]); return *this; }
char * toString(double d) { sprintf(tmp, "%lf%c", d, '\0'); return tmp; }
inline IO& operator << (double d) { return (*this) << toString(d); }
#define defineOutFor(intType) inline char * toString(intType n) { char * p = (tmp + 30); \
if (n) { bool isNeg = 0; if (n < 0) isNeg = 1, n = -n; while (n) *--p = (n % 10) + '0', n /= 10; \
if (isNeg) *--p = '-'; } else *--p = '0'; return p; } inline IO& operator << (intType n) { return (*this) << toString(n); }
defineOutFor(int)defineOutFor(long long)
#define endl ('\n')
#define cout __io__
#define cin __io__
} __io__;
/**************************************************************************************************/
const int N = 4001;
char a[N][N];
int d[N][N];
int d_x[] = {1, -1, 0, 0};
int d_y[] = {0, 0, 1, -1};
int H, W;
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
H = readInt(), W = readInt();
for (int i = 1; i <= H; i++) {
for (int j = 1; j <= W; j++) {
cin >> a[i][j];
d[i][j] = MOD;
}
}
deque<pair <int, int> > q;
q.push_front({1, 1});
d[1][1] = 0;
int mx = 0;
while (!q.empty()) {
pair <int, int> v = q.front();
q.pop_front();
int x = v.F;
int y = v.S;
//cerr << v.F << ' ' << v.S << endl;
for (int i = 0; i < 4; i++) {
int X = v.first + d_x[i];
int Y = v.second + d_y[i];
if (X >= 1 && Y >= 1 && X <= H && Y <= W && a[X][Y] != '.') {
if (d[X][Y] > d[x][y] + (a[X][Y] != a[x][y])) {
d[X][Y] = d[x][y] + (a[X][Y] != a[x][y]);
if ((a[X][Y] != a[x][y])) {
q.push_front({X, Y});
} else {
q.pb({X, Y});
}
}
}
}
}
for (int i =1 ; i <= H; i++) {
for (int j = 1; j <= W; j++) {
if (a[i][j] != '.')
mx = max(mx, d[i][j]);
//cout << d[i][j] << ' ';
}
//cout << endl;
}
cout << mx+1;
return 0;
}
Compilation message
tracks.cpp:99:0: warning: "endl" redefined
#define endl ('\n')
tracks.cpp:32:0: note: this is the location of the previous definition
#define endl '\n'
tracks.cpp: In function 'int main()':
tracks.cpp:119:6: error: 'struct IO' has no member named 'tie'
cin.tie(0);
^~~
tracks.cpp:120:7: error: 'struct IO' has no member named 'tie'
cout.tie(0);
^~~
