Language: C++

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; }

/* attention
    long longのシフト演算には気をつけよう
    タイポした時のデバッグが死ぬほどきつくなるので変数名は最低3字くらい使った方がいいかも
    sizeは(int)とキャストしよう
    ごちゃごちゃ場合分けを考える前に全探索は考えましたか？
*/

const ll mod = 1e9+7;

void chmod(ll &M){
    if(M >= mod) M %= mod;
    else if(M < 0){
        M += (abs(M)/mod + 1)*mod;
        M %= mod;
    }
}

ll modpow(ll x, ll n){
    if(n == 0) return 1;

    ll res = modpow(x, n/2);
    if(n%2 == 0) return res*res%mod;
    else return res*res%mod*x%mod;
}

ll power(ll x, ll n){
    if(n == 0) return 1;

    ll res = power(x, n/2);
    if(n%2 == 0) return res*res;
    else return res*res*x;
}

int getl(int i, int N) { return i==0? N-1:i-1; };
int getr(int i, int N) { return i==N-1? 0:i+1; };

/* <--------------------------------------------> */

struct s{
    int h1, w1, h2, w2;
};

int main(){
    cin.tie(0);
    ios::sync_with_stdio(false);

    int h, w; cin >> h >> w;
    vector< vector<int> > a(h+5, vector<int>(w+5, 0));
    for(int i=1; i<=h; ++i) for(int j=1; j<=w; ++j) cin >> a[i][j];

    vector
 ans;

    for(int i=1; i<=h; ++i){
        if(i%2 == 1){
            for(int j=1; j<=w; ++j) if(a[i][j]%2 == 1) {
                if(i==h && j==w) continue;
                else if(j == w) { ans.push_back({i, j, i+1, j}); ++a[i+1][j]; }
                else { ans.push_back({i, j, i, j+1}); ++a[i][j+1]; }
            }
        }
        else{
            for(int j=w; j>0; --j) if(a[i])[j]%2 == 1) {
                if(i==h && j==1) continue;
                else if(j == 1) { ans.push_back({i, j, i+1, j}); ++a[i+1][j]; }
                else { ans.push_back({i, j, i, j-1}); ++a[i][j-1]; }
            }
        }
    }

    cout << ans.size() << endl;
    for(auto s:ans) printf("%d %d %d %d\n", s.h1, s.w1, s.h2, s.w2);

	return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:69:43: error: could not convert 'a.std::vector<std::vector<int> >::operator[](((std::vector<std::vector<int> >::size_type)i))' from '__gnu_cxx::__alloc_traits<std::allocator<std::vector<int> >, std::vector<int> >::value_type' {aka 'std::vector<int>'} to 'bool'
   69 |             for(int j=w; j>0; --j) if(a[i])[j]%2 == 1) {
      |                                           ^
      |                                           |
      |                                           __gnu_cxx::__alloc_traits<std::allocator<std::vector<int> >, std::vector<int> >::value_type {aka std::vector<int>}
a.cc: In lambda function:
a.cc:69:47: error: expected '{' before '%' token
   69 |             for(int j=w; j>0; --j) if(a[i])[j]%2 == 1) {
      |                                               ^
a.cc: In function 'int main()':
a.cc:69:47: error: no match for 'operator%' (operand types are 'main()::<lambda()>' and 'int')
   69 |             for(int j=w; j>0; --j) if(a[i])[j]%2 == 1) {
      |                                            ~~~^~
      |                                            |   |
      |                                            |   int
      |                                            main()::<lambda()>
In file included from /usr/include/c++/14/valarray:605,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:166,
                 from a.cc:1:
/usr/include/c++/14/bits/valarray_after.h:409:5: note: candidate: 'template<class _Dom1, class _Dom2> std::_Expr<std::__detail::_BinClos<std::__modulus, std::_Expr, std::_Expr, _Dom1, _Dom2>, typename std::__fun<std::__modulus, typename _Dom1::value_type>::result_type> std::operator%(const _Expr<_Dom1, typename _Dom1::value_type>&, const _Expr<_Dom2, typename _Dom2::value_type>&)'
  409 |     _DEFINE_EXPR_BINARY_OPERATOR(%, struct std::__modulus)
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/valarray_after.h:409:5: note:   template argument deduction/substitution failed:
a.cc:69:48: note:   'main()::<lambda()>' is not derived from 'const std::_Expr<_Dom1, typename _Dom1::value_type>'
   69 |             for(int j=w; j>0; --j) if(a[i])[j]%2 == 1) {
      |                                                ^
/usr/include/c++/14/bits/valarray_after.h:409:5: note: candidate: 'template<class _Dom> std::_Expr<std::__detail::_BinClos<std::__modulus, std::_Expr, std::_Constant, _Dom, typename _Dom::value_type>, typename std::__fun<std::__modulus, typename _Dom1::value_type>::result_type> std::operator%(const _Expr<_Dom1, typename _Dom1::value_type>&, const typename _Dom::value_type&)'
  409 |     _DEFINE_EXPR_BINARY_OPERATOR(%, struct std::__modulus)
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/valarray_after.h:409:5: note:   template argument deduction/substitution failed:
a.cc:69:48: note:   'main()::<lambda()>' is not derived from 'const std::_Expr<_Dom1, typename _Dom1::value_type>'
   69 |             for(int j=w; j>0; --j) if(a[i])[j]%2 == 1) {
      |                                                ^
/usr/include/c++/14/bits/valarray_after.h:409:5: note: candidate: 'template<class _Dom> std::_Expr<std::__detail::_BinClos<std::__modulus, std::_Constant, std::_Expr, typename _Dom::value_type, _Dom>, typename std::__fun<std::__modulus, typename _Dom1::value_type>::result_type> std::operator%(const typename _Dom::value_type&, const _Expr<_Dom1, typename _Dom1::value_type>&)'
  409 |     _DEFINE_EXPR_BINARY_OPERATOR(%, struct std::__modulus)
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/valarray_after.h:409:5: note:   template argument deduction/substitution failed:
a.cc:69:48: note:   mismatched types 'const std::_Expr<_Dom1, typename _Dom1::value_type>' and 'int'
   69 |             for(int j=w; j>0; --j) if(a[i])[j]%2 == 1) {
      |                                                ^
/usr/include/c++/14/bits/valarray_after.h:409:5: note: candidate: 'template<class _Dom> std::_Expr<std::__detail::_BinClos<std::__modulus, std::_Expr, std::_ValArray, _Dom, typename _Dom::value_type>, typename std::__fun<std::__modulus, typename _Dom1::value_type>::result_type> std::operator%(const _Expr<_Dom1, typename _Dom1::value_type>&, const valarray<typename _Dom::value_type>&)'
  409 |     _DEFINE_EXPR_BINARY_OPERATOR(%, struct std::__modulus)
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/valarray_after.h:409:5: note:   template argument deduction/substitution failed:
a.cc:69:48: note:   'main()::<lambda()>' is not derived from 'const std::_Expr<_Dom1, typename _Dom1::value_type>'
   69 |             for(int j=w; j>0; --j) if(a[i])[j]%2 == 1) {
      |                                                ^
/usr/include/c++/14/bits/valarray_after.h:409:5: note: candidate: 'template<class _Dom> std::_Expr<std::__detail::_BinClos<std::__modulus, std::_ValArray, std::_Expr, typename _Dom::value_type, _Dom>, typename std::__fun<std::__modulus, typename _Dom1::value_type>::result_type> std::operator%(const valarray<typename _Dom::value_type>&, const _Expr<_Dom1, typename _Dom1::value_type>&)'
  409 |     _DEFINE_EXPR_BINARY_OPERATOR(%, struct std::__modulus)
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/valarray_after.h:409:5: note:   template argument deduction/substitution failed:
a.cc:69:48: note:   mismatched types 'const std::_Expr<_Dom1, typename _Dom1::value_type>' and 'int'
   69 |             for(int j=w; j>0; --j) if(a[i])[j]%2 == 1) {
      |                                                ^
/usr/include/c++/14/valarray:1200:1: note: candidate: 'template<class _Tp> std::_Expr<std::__detail::_BinClos<std::__modulus, std::_ValArray, std::_ValArray, _Tp, _Tp>, typename std::__fun<std::__modulus, _Tp>::result_type> std::operator%(const valarray<_Tp>&, const valarray<_Tp>&)'
 1200 | _DEFINE_BINARY_OPERATOR(%, __modulus)
      | ^~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/valarray:1200:1: note:   template argument deduction/substitution failed:
a.cc:69:48: note:   'main()::<lambda()>' is not derived from 'const std::valarray<_Tp>'
   69 |             for(int j=w; j>0; --j) if(a[i])[j]%2 == 1) {
      |                                                ^
/usr/include/c++/14/valarray:1200:1: note: candidate: 'template<class _Tp> std::_Expr<std::__detail::_BinClos<std::__modulus, std::_ValArray, std::_Constant, _Tp, _Tp>, typename std::__fun<std::__modulus, _Tp>::result_type> std::operator%(const valarray<_Tp>&, const typename valarray<_Tp>::value_type&)'
 1200 | _DEFINE_BINARY_OPERATOR(%, __modulus)
      | ^~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/valarray:1200:1: note:   template argument deduction/substitution failed:
a.cc:69:48: note:   'main()::<lambda()>' is not derived from 'const std::valarray<_Tp>'
   69 |             for(int j=w; j>0; --j) if(a[i])[j]%2 == 1) {
      |                                                ^
/usr/include/c++/14/valarray:1200:1: note: candidate: 'template<class _Tp> std::_Expr<std::__detail::_BinClos<std::__modulus, std::_Constant, std::_ValArray, _Tp, _Tp>, typename std::__fun<std::__modulus, _Tp>::result_type> std::operator%(const typename valarray<_Tp>::value_type&, const valarray<_Tp>&)'
 1200 | _DEFINE_BINARY_OPERATOR(%, __modulus)
      | ^~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/valarray:1200:1: note:   template argument deduction/substitution failed:
a.cc:69:48: note:   mismatched types 'const std::valarray<_Tp>' and 'int'
   69 |             for(int j=w; j>0; --j) if(a[i])[j]%2 == 1) {
      |                                                ^