Could anyone hint me why this code fails to compile with error?↵
↵
`g.cpp: In lambda function:`↵
`g.cpp:66:36: error: inconsistent types ‘bool’ and ‘std::_Bit_reference’ deduced for lambda return type`↵
` 66 | return was[n - 1][m - 1];`↵
↵
If i explicitely do ↵
↵
↵
~~~~~↵
const auto bfs = [&](int del) -> bool {↵
~~~~~↵
it compiles ok.↵
↵
↵
<spoiler summary="code">↵
↵
~~~~~↵
#include<bits/stdc++.h>↵
using namespace std;↵
↵
void __print(int x) {cerr << x;}↵
void __print(long x) {cerr << x;}↵
void __print(long long x) {cerr << x;}↵
void __print(unsigned x) {cerr << x;}↵
void __print(unsigned long x) {cerr << x;}↵
void __print(unsigned long long x) {cerr << x;}↵
void __print(float x) {cerr << x;}↵
void __print(double x) {cerr << x;}↵
void __print(long double x) {cerr << x;}↵
void __print(char x) {cerr << '\'' << x << '\'';}↵
void __print(const char *x) {cerr << '\"' << x << '\"';}↵
void __print(const string &x) {cerr << '\"' << x << '\"';}↵
void __print(bool x) {cerr << (x ? "true" : "false");}↵
↵
template<typename T, typename V>↵
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ", "; __print(x.second); cerr << '}';}↵
template<typename T>↵
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? ", " : ""), __print(i); cerr << "}";}↵
void _print() {cerr << "]\n";}↵
template <typename T, typename... V>↵
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}↵
#ifndef ONLINE_JUDGE ↵
#define dbg(x...) cerr << "\e[91m"<<__func__<<":"<<__LINE__<<" [" << #x << "] = ["; _print(x); cerr << "\e[39m" << endl;↵
#else↵
#define dbg(x...)↵
#endif↵
↵
int main() {↵
#ifndef ONLINE_JUDGE↵
freopen("input.txt", "r", stdin);↵
#endif↵
cin.tie(0)->sync_with_stdio(0);↵
int nsc;↵
cin >> nsc;↵
for(int sc = 0; sc < nsc; sc++) {↵
int n, m;↵
cin >> n >> m;↵
vector<vector<int>> a(n, vector<int>(m));↵
for(int i = 0; i < n; i++)↵
for(int j = 0; j < m; j++)↵
cin >> a[i][j];↵
vector<vector<bool>> was(n, vector<bool>(m, false));↵
const auto bfs = [&](int del) {↵
for(int i = 0; i < n; i++)↵
for(int j = 0; j < m; j++)↵
was[i][j] = false;↵
was[0][0] = true;↵
for(int j = 1; j < m; j++)↵
was[0][j] = (a[0][j] % del == 0 && was[0][j-1]);↵
for(int i = 1; i < n; i++){↵
bool some = false;↵
for(int j = 0; j < m; j++) ↵
if (a[i][j] % del == 0) {↵
was[i][j] = was[i - 1][j];↵
if (j > 0)↵
was[i][j] = was[i][j] || was[i][j - 1];↵
some = some || was[i][j];↵
}↵
if (!some) return false;↵
↵
// cout << "dbg " << i << " " << j << " " << was[i][j] << "\n";↵
}↵
return was[n - 1][m - 1];↵
};↵
↵
int res = 1;↵
for(int i = 1; i * i <= a[0][0]; i++) ↵
if (a[0][0] % i == 0) {↵
if (bfs(a[0][0] / i)) {↵
res = max(res, a[0][0] / i);↵
break;↵
}↵
if (bfs(i))↵
res = max(res, i);↵
}↵
cout << res << "\n";↵
}↵
↵
return 0;↵
}↵
~~~~~↵
↵
↵
</spoiler>↵
↵
↵
`g.cpp: In lambda function:`↵
`g.cpp:66:36: error: inconsistent types ‘bool’ and ‘std::_Bit_reference’ deduced for lambda return type`↵
` 66 | return was[n - 1][m - 1];`↵
↵
If i explicitely do ↵
↵
↵
~~~~~↵
const auto bfs = [&](int del) -> bool {↵
~~~~~↵
it compiles ok.↵
↵
↵
<spoiler summary="code">↵
↵
~~~~~↵
#include<bits/stdc++.h>↵
using namespace std;↵
↵
void __print(int x) {cerr << x;}↵
void __print(long x) {cerr << x;}↵
void __print(long long x) {cerr << x;}↵
void __print(unsigned x) {cerr << x;}↵
void __print(unsigned long x) {cerr << x;}↵
void __print(unsigned long long x) {cerr << x;}↵
void __print(float x) {cerr << x;}↵
void __print(double x) {cerr << x;}↵
void __print(long double x) {cerr << x;}↵
void __print(char x) {cerr << '\'' << x << '\'';}↵
void __print(const char *x) {cerr << '\"' << x << '\"';}↵
void __print(const string &x) {cerr << '\"' << x << '\"';}↵
void __print(bool x) {cerr << (x ? "true" : "false");}↵
↵
template<typename T, typename V>↵
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ", "; __print(x.second); cerr << '}';}↵
template<typename T>↵
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? ", " : ""), __print(i); cerr << "}";}↵
void _print() {cerr << "]\n";}↵
template <typename T, typename... V>↵
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}↵
#ifndef ONLINE_JUDGE ↵
#define dbg(x...) cerr << "\e[91m"<<__func__<<":"<<__LINE__<<" [" << #x << "] = ["; _print(x); cerr << "\e[39m" << endl;↵
#else↵
#define dbg(x...)↵
#endif↵
↵
int main() {↵
#ifndef ONLINE_JUDGE↵
freopen("input.txt", "r", stdin);↵
#endif↵
cin.tie(0)->sync_with_stdio(0);↵
int nsc;↵
cin >> nsc;↵
for(int sc = 0; sc < nsc; sc++) {↵
int n, m;↵
cin >> n >> m;↵
vector<vector<int>> a(n, vector<int>(m));↵
for(int i = 0; i < n; i++)↵
for(int j = 0; j < m; j++)↵
cin >> a[i][j];↵
vector<vector<bool>> was(n, vector<bool>(m, false));↵
const auto bfs = [&](int del) {↵
for(int i = 0; i < n; i++)↵
for(int j = 0; j < m; j++)↵
was[i][j] = false;↵
was[0][0] = true;↵
for(int j = 1; j < m; j++)↵
was[0][j] = (a[0][j] % del == 0 && was[0][j-1]);↵
for(int i = 1; i < n; i++){↵
bool some = false;↵
for(int j = 0; j < m; j++) ↵
if (a[i][j] % del == 0) {↵
was[i][j] = was[i - 1][j];↵
if (j > 0)↵
was[i][j] = was[i][j] || was[i][j - 1];↵
some = some || was[i][j];↵
}↵
if (!some) return false;↵
↵
// cout << "dbg " << i << " " << j << " " << was[i][j] << "\n";↵
}↵
return was[n - 1][m - 1];↵
};↵
↵
int res = 1;↵
for(int i = 1; i * i <= a[0][0]; i++) ↵
if (a[0][0] % i == 0) {↵
if (bfs(a[0][0] / i)) {↵
res = max(res, a[0][0] / i);↵
break;↵
}↵
if (bfs(i))↵
res = max(res, i);↵
}↵
cout << res << "\n";↵
}↵
↵
return 0;↵
}↵
~~~~~↵
↵
↵
</spoiler>↵
↵
