dango_maker.cpp: In function 'void fre(std::string)':
dango_maker.cpp:41:27: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
41 | void fre(string s){freopen((s+".in").c_str(),"r",stdin);freopen((s+".out").c_str(),"w",stdout);}
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
dango_maker.cpp:41:64: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
41 | void fre(string s){freopen((s+".in").c_str(),"r",stdin);freopen((s+".out").c_str(),"w",stdout);}
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
dango_maker.cpp: In function 'void solve()':
dango_maker.cpp:71:13: warning: writing 1 byte into a region of size 0 [-Wstringop-overflow=]
71 | a[i][j]=a[i][j+r[i][j]]=a[i][j+r[i][j+r[i][j]+r[i][j]]]=0;
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
dango_maker.cpp:51:6: note: at offset 0 to object 'a' with size 9042049 declared here
51 | char a[N][N];
| ^
dango_maker.cpp:79:33: warning: writing 1 byte into a region of size 0 [-Wstringop-overflow=]
79 | a[i][j]=a[i+1][j]=a[i+2][j]=0;
| ~~~~~~~~~^~
dango_maker.cpp:51:6: note: at offset 0 to object 'a' with size 9042049 declared here
51 | char a[N][N];
| ^
dango_maker.cpp:79:23: warning: writing 1 byte into a region of size 0 [-Wstringop-overflow=]
79 | a[i][j]=a[i+1][j]=a[i+2][j]=0;
| ~~~~~~~~~^~~~~~~~~~~~
dango_maker.cpp:51:6: note: at offset 0 to object 'a' with size 9042049 declared here
51 | char a[N][N];
| ^
dango_maker.cpp:79:13: warning: writing 1 byte into a region of size 0 [-Wstringop-overflow=]
79 | a[i][j]=a[i+1][j]=a[i+2][j]=0;
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
dango_maker.cpp:51:6: note: at offset 0 to object 'a' with size 9042049 declared here
51 | char a[N][N];
| ^