Compilare: user.cpp: In function ‘void solve()’: user.cpp:114:9: warning: unused variable ‘i’ [-Wunused-variable] int i, j; ^ user.cpp:114:12: warning: unused variable ‘j’ [-Wunused-variable] int i, j; ^ user.cpp: In function ‘void readFile()’: user.cpp:15:30: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d%d", &n, &m); ^ user.cpp:22:109: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d", &a[i][j]), col[j] += a[i][j], lin[i] += a[i][j], s += a[i][j], b[i][j] = a[i][j]; ^