Compilare: main.cpp:1:2: warning: #import is a deprecated GCC extension [-Wdeprecated] #import<bits/stdc++.h> ^~~~~~ main.cpp: In function 'int M(int, int)': main.cpp:4:283: warning: no return statement in function returning non-void [-Wreturn-type] std::ifstream I{"ferma3.in"};std::ofstream O{"ferma3.out"};char a[N][N],r,e;int b[N][N],w[]={-1,0,1,0},t[]={0,1,0,-1},d[N*N],n,m,z,i,j,k,l,u,s,v,o,p,q,c[N*N];int M(int x,int y){b[x][y]=z;d[z]++;for(int i=0;i<4;i++)if(!b[x+w[i]][y+t[i]]&&a[x][y]==a[x+w[i]][y+t[i]])M(x+w[i], y+t[i]);}main(){I>>v>>n>>m;for(i=1;i<=n;i++)I>>a[i]+1;F if(!b[i][j]){z++;M(i,j);if(o<d[z])o=d[z];}F{e=a[i][j];for(k=0;k<4;k++){a[i][j]=a[i+w[k]][j+t[k]];for(l=0,s=0;l<4;l++)if(!c[b[i+w[l]][j+t[l]]]&&a[i][j]==a[i+w[l]][j+t[l]])c[b[i+w[l]][j+t[l]]]=1,s+=d[b[i+w[l]][j+t[l]]];if(!c[b[i][j]])s++;if(s>u)u=s,r=a[i][j],p=i,q=j;for(l=0;l<4;l++)c[b[i+w[l]][j+t[l]]]=0;}a[i][j]=e;}v&1?O<<o<<"\n":O<<p<<" "<<q<<"\n"<<r<<"\n";} ^ main.cpp: At global scope: main.cpp:4:289: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type] std::ifstream I{"ferma3.in"};std::ofstream O{"ferma3.out"};char a[N][N],r,e;int b[N][N],w[]={-1,0,1,0},t[]={0,1,0,-1},d[N*N],n,m,z,i,j,k,l,u,s,v,o,p,q,c[N*N];int M(int x,int y){b[x][y]=z;d[z]++;for(int i=0;i<4;i++)if(!b[x+w[i]][y+t[i]]&&a[x][y]==a[x+w[i]][y+t[i]])M(x+w[i], y+t[i]);}main(){I>>v>>n>>m;for(i=1;i<=n;i++)I>>a[i]+1;F if(!b[i][j]){z++;M(i,j);if(o<d[z])o=d[z];}F{e=a[i][j];for(k=0;k<4;k++){a[i][j]=a[i+w[k]][j+t[k]];for(l=0,s=0;l<4;l++)if(!c[b[i+w[l]][j+t[l]]]&&a[i][j]==a[i+w[l]][j+t[l]])c[b[i+w[l]][j+t[l]]]=1,s+=d[b[i+w[l]][j+t[l]]];if(!c[b[i][j]])s++;if(s>u)u=s,r=a[i][j],p=i,q=j;for(l=0;l<4;l++)c[b[i+w[l]][j+t[l]]]=0;}a[i][j]=e;}v&1?O<<o<<"\n":O<<p<<" "<<q<<"\n"<<r<<"\n";} ^ main.cpp: In function 'int main()': main.cpp:4:326: warning: suggest parentheses around '+' inside '>>' [-Wparentheses] std::ifstream I{"ferma3.in"};std::ofstream O{"ferma3.out"};char a[N][N],r,e;int b[N][N],w[]={-1,0,1,0},t[]={0,1,0,-1},d[N*N],n,m,z,i,j,k,l,u,s,v,o,p,q,c[N*N];int M(int x,int y){b[x][y]=z;d[z]++;for(int i=0;i<4;i++)if(!b[x+w[i]][y+t[i]]&&a[x][y]==a[x+w[i]][y+t[i]])M(x+w[i], y+t[i]);}main(){I>>v>>n>>m;for(i=1;i<=n;i++)I>>a[i]+1;F if(!b[i][j]){z++;M(i,j);if(o<d[z])o=d[z];}F{e=a[i][j];for(k=0;k<4;k++){a[i][j]=a[i+w[k]][j+t[k]];for(l=0,s=0;l<4;l++)if(!c[b[i+w[l]][j+t[l]]]&&a[i][j]==a[i+w[l]][j+t[l]])c[b[i+w[l]][j+t[l]]]=1,s+=d[b[i+w[l]][j+t[l]]];if(!c[b[i][j]])s++;if(s>u)u=s,r=a[i][j],p=i,q=j;for(l=0;l<4;l++)c[b[i+w[l]][j+t[l]]]=0;}a[i][j]=e;}v&1?O<<o<<"\n":O<<p<<" "<<q<<"\n"<<r<<"\n";} ~~~~^~