Compilare: main.cpp: In function 'int main()': main.cpp:4:30: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("nks.in","r",stdin); ^ main.cpp:5:32: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("nks.out","w",stdout); ^ main.cpp:7:37: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d%d",&n,&m,&a,&b,&c); ^ main.cpp:15:9: warning: 'pi' may be used uninitialized in this function [-Wmaybe-uninitialized] pi++; ^