Language: C++

#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

#define ll long long int
#define pb push_back
#define eb emplace_back
#define xx first
#define yy second
#define INF 0x3f3f3f3f

using namespace std;
using namespace __gnu_pbds;

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
typedef tree<pair<int,int>,null_type, less<pair<int,int>>,rb_tree_tag,tree_order_statistics_node_update>   ordered_set;
const int N=1e5+10, mod=1e9+7;
ll dp[N][110];

int main(){
	ios_base::sync_with_stdio(0);	cin.tie(0);
	int n,m,i,j;
	cin>>n>>m;
	vector<vector<char>> a(n+1,vector<char>(m+1));
	ll dp[n+1][m+1];
	for(i=1;i<=n;i++)for(j=1;j<=m;j++) cin>>a[i][j];
	for(i=0;i<=n;i++)dp[i][0]=0;
	for(i=0;i<=m;i++)dp[0][i]=0;
	
	dp[1][1]=1;
	for(i=1;i<=n;i++){
		for(j=(i==1?2:1);j<=m;j++){
			if(a[i][j]=='#') dp[i][j]=0;
			else dp[i][j]=(dp[i-1][j]+dp[i][j-1])%mod;
		}
	}
	cout<<dp[n][m];
	
}
// check for any potential overflow before submitting
#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

#define ll long long int
#define pb push_back
#define eb emplace_back
#define xx first
#define yy second
#define INF 0x3f3f3f3f

using namespace std;
using namespace __gnu_pbds;

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
typedef tree<pair<int,int>,null_type, less<pair<int,int>>,rb_tree_tag,tree_order_statistics_node_update>   ordered_set;
const int N=1e5+10, mod=1e9+7;
ll dp[N][110];

int main(){
	ios_base::sync_with_stdio(0);	cin.tie(0);
	int n,m,i,j;
	cin>>n>>m;
	vector<vector<char>> a(n+1,vector<char>(m+1));
	ll dp[n+1][m+1];
	for(i=1;i<=n;i++)for(j=1;j<=m;j++) cin>>a[i][j];
	for(i=0;i<=n;i++)dp[i][0]=0;
	for(i=0;i<=m;i++)dp[0][i]=0;
	
	dp[1][1]=1;
	for(i=1;i<=n;i++){
		for(j=(i==1?2:1);j<=m;j++){
			if(a[i][j]=='#') dp[i][j]=0;
			else dp[i][j]=(dp[i-1][j]+dp[i][j-1])%mod;
		}
	}
	cout<<dp[n][m];
	
}
// check for any potential overflow before submitting


Compiler output:
a.cc:55:9: error: redefinition of 'std::mt19937 rng'
   55 | mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
      |         ^~~
a.cc:15:9: note: 'std::mt19937 rng' previously declared here
   15 | mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
      |         ^~~
a.cc:57:11: error: redefinition of 'const int N'
   57 | const int N=1e5+10, mod=1e9+7;
      |           ^
a.cc:17:11: note: 'const int N' previously defined here
   17 | const int N=1e5+10, mod=1e9+7;
      |           ^
a.cc:57:21: error: redefinition of 'const int mod'
   57 | const int N=1e5+10, mod=1e9+7;
      |                     ^~~
a.cc:17:21: note: 'const int mod' previously defined here
   17 | const int N=1e5+10, mod=1e9+7;
      |                     ^~~
a.cc:58:4: error: redefinition of 'long long int dp [100010][110]'
   58 | ll dp[N][110];
      |    ^~
a.cc:18:4: note: 'long long int dp [100010][110]' previously declared here
   18 | ll dp[N][110];
      |    ^~
a.cc:60:5: error: redefinition of 'int main()'
   60 | int main(){
      |     ^~~~
a.cc:20:5: note: 'int main()' previously defined here
   20 | int main(){
      |     ^~~~