Compilare: user.cpp: In function ‘int main()’: user.cpp:32:10: warning: unused variable ‘j’ [-Wunused-variable] int i, j; ^ user.cpp:35:45: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d %d %d %d", &N, &M, &S, &D); ^ user.cpp:37:33: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d %d", &x, &y); ^ user.cpp:45:32: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d", &cost[i]); ^