/in/foo.cc: In function 'void getmu()':
/in/foo.cc:26:25: warning: iteration 50004 invokes undefined behavior [-Waggressive-loop-optimizations]
     sum[i]=sum[i-1]+mu[i];
                     ~~~~^
/in/foo.cc:25:18: note: within this loop
     for(int i=1;i<=MAXN;i++)
                  ^
/in/foo.cc:17:18: warning: iteration 50003 invokes undefined behavior [-Waggressive-loop-optimizations]
         if(!jud[i])pri[++cnt]=i,mu[i]=-1;
             ~~~~~^
/in/foo.cc:15:18: note: within this loop
     for(int i=2;i<=MAXN;i++)
                  ^