#include <bits/stdc++.h>
// #include <atcoder/all>
using namespace std;
#define int long long
#define all(x) (x).begin(), (x).end()
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<pair<int, int>> vpi;
typedef pair<int, int> pi;
#define f first
#define s second
#define pb push_back
#define endl "\n"
#define yes cout << "YES" << endl
#define no cout << "NO" << endl
int dx[] = {-1, 0, 1, 0};
int dy[] = {0, 1, 0, -1};
const int mod1 = 1e9 + 7, mod2 = 998244353, INF = 2e18, N = 2e5 + 5, L = 19;
int gcd(int a, int b) { return b == 0 ? a : gcd(b, a % b); }
// -----------------------------------------------------------------------------
int n, m, depth[N][N];
string snow[N];
bool inside(int x, int y)
{
return (x >= 0 && x < n && y >= 0 && y < m && snow[x][y] != '.');
}
void solve()
{
cin >> n >> m;
for (int i = 0; i < n; i++)
{
cin >> snow[i];
fill(depth[i], depth[i] + m, 0);
}
int ans = 0;
deque<pi> dq;
dq.push_back({0, 0});
depth[0][0] = 1;
while (!dq.empty())
{
auto [x, y] = dq.front();
dq.pop_front();
ans = max(ans, depth[x][y]);
for (int i = 0; i < 4; i++)
{
int newx = x + dx[i], newy = y + dy[i];
if (inside(newx, newy) && depth[newx][newy] == 0)
{
if (snow[x][y] == snow[newx][newy])
{
depth[newx][newy] = depth[x][y];
dq.push_front({newx, newy});
}
else
{
depth[newx][newy] = depth[x][y] + 1;
dq.push_back({newx, newy});
}
}
}
}
cout << ans << endl;
}
signed main()
{
// __START__;
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
int t = 1;
cin >> t;
while (t--)
{
solve();
}
// __END__;
return 0;
}
Compilation message (stderr)
/tmp/ccIDsoFk.o: in function `inside(long long, long long)':
tracks.cpp:(.text+0xa1): relocation truncated to fit: R_X86_64_PC32 against symbol `n' defined in .bss section in /tmp/ccIDsoFk.o
tracks.cpp:(.text+0xb3): relocation truncated to fit: R_X86_64_PC32 against symbol `m' defined in .bss section in /tmp/ccIDsoFk.o
/tmp/ccIDsoFk.o: in function `solve()':
tracks.cpp:(.text+0x1c9): relocation truncated to fit: R_X86_64_PC32 against symbol `n' defined in .bss section in /tmp/ccIDsoFk.o
tracks.cpp:(.text+0x1dd): relocation truncated to fit: R_X86_64_PC32 against symbol `std::cin' defined in .bss._ZSt3cin section in /usr/lib/gcc/x86_64-linux-gnu/11/libstdc++.a(globals_io.o)
tracks.cpp:(.text+0x211): relocation truncated to fit: R_X86_64_PC32 against symbol `m' defined in .bss section in /tmp/ccIDsoFk.o
tracks.cpp:(.text+0x220): relocation truncated to fit: R_X86_64_PC32 against symbol `n' defined in .bss section in /tmp/ccIDsoFk.o
tracks.cpp:(.text+0x245): relocation truncated to fit: R_X86_64_PC32 against symbol `m' defined in .bss section in /tmp/ccIDsoFk.o
tracks.cpp:(.text+0x26d): relocation truncated to fit: R_X86_64_PC32 against symbol `n' defined in .bss section in /tmp/ccIDsoFk.o
tracks.cpp:(.text+0x3f9): relocation truncated to fit: R_X86_64_PC32 against symbol `n' defined in .bss section in /tmp/ccIDsoFk.o
tracks.cpp:(.text+0x43b): relocation truncated to fit: R_X86_64_PC32 against symbol `std::cout' defined in .bss._ZSt4cout section in /usr/lib/gcc/x86_64-linux-gnu/11/libstdc++.a(globals_io.o)
tracks.cpp:(.text+0x493): additional relocation overflows omitted from the output
/usr/lib/gcc/x86_64-linux-gnu/11/libstdc++.a(ios_init.o): in function `std::ios_base::Init::Init()':
(.text._ZNSt8ios_base4InitC2Ev+0x1c): failed to convert GOTPCREL relocation against '_ZNSt8ios_base4Init11_S_refcountE'; relink with --no-relax
(.text._ZNSt8ios_base4InitC2Ev+0x1c6): failed to convert GOTPCREL relocation against '_ZSt4cout'; relink with --no-relax
(.text._ZNSt8ios_base4InitC2Ev+0x260): failed to convert GOTPCREL relocation against '_ZSt3cin'; relink with --no-relax
(.text._ZNSt8ios_base4InitC2Ev+0x2e2): failed to convert GOTPCREL relocation against '_ZSt4cerr'; relink with --no-relax
(.text._ZNSt8ios_base4InitC2Ev+0x353): failed to convert GOTPCREL relocation against '_ZSt4clog'; relink with --no-relax
(.text._ZNSt8ios_base4InitC2Ev+0x541): failed to convert GOTPCREL relocation against '_ZSt5wcout'; relink with --no-relax
(.text._ZNSt8ios_base4InitC2Ev+0x5e5): failed to convert GOTPCREL relocation against '_ZSt4wcin'; relink with --no-relax
(.text._ZNSt8ios_base4InitC2Ev+0x670): failed to convert GOTPCREL relocation against '_ZSt5wcerr'; relink with --no-relax
(.text._ZNSt8ios_base4InitC2Ev+0x6e9): failed to convert GOTPCREL relocation against '_ZSt5wclog'; relink with --no-relax
collect2: error: ld returned 1 exit status
