Compilare: main.cpp: In function 'int main()': main.cpp:9:29: warning: unused variable 'nr1' [-Wunused-variable] int j,k,a,b,n,x,y,con,i,nr1,nr2; ^~~ main.cpp:9:33: warning: unused variable 'nr2' [-Wunused-variable] int j,k,a,b,n,x,y,con,i,nr1,nr2; ^~~ main.cpp:7:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("defrag.in","r",stdin); ^ main.cpp:8:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("defrag.out","w",stdout); ^ main.cpp:10:34: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d",&k,&a,&b,&n); ^ main.cpp:13:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&x,&y); ^