Compilare: user.cpp: In function ‘int main()’: user.cpp:11:61: warning: unused variable ‘y’ [-Wunused-variable] int i,j,i1,i2,s,smax,sol,m,n,k,a[501][501]={0},nr=0,x=0,y,r,l; ^ user.cpp:11:63: warning: unused variable ‘r’ [-Wunused-variable] int i,j,i1,i2,s,smax,sol,m,n,k,a[501][501]={0},nr=0,x=0,y,r,l; ^ user.cpp:11:65: warning: unused variable ‘l’ [-Wunused-variable] int i,j,i1,i2,s,smax,sol,m,n,k,a[501][501]={0},nr=0,x=0,y,r,l; ^ user.cpp:12:32: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d%d%d",&m,&n,&k); ^ user.cpp:14:52: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for (j=1;j<=n;j++) {fscanf(f,"%d",&a[i][j]);if (a[i][j]) x++;} ^