Compilare: user.cpp: In function ‘int main()’: user.cpp:116:70: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d %d %d %d %d %d %d", &N, &K1, &K2, &L1, &C1, &L2, &C2); ^ user.cpp:119:35: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%hd", &val[i][j]); ^ user.cpp:162:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("vis.out", "w", stdout); ^