Submission #974256

#	Time	Username	Problem	Language	Result	Execution time	Memory
974256		vjudge1	Bitwise (BOI06_bitwise)	C11	100 / 100	1 ms	348 KiB

bitwise

#include<stdio.h>

#define N 10000
int lena[N],n,p,k[N],at[N+1];long long z,l[N],r[N];

int main()
{
    scanf("%d%d",&n,&p);
    for(int i=0;i<p;++i)
        scanf("%d",k+i);
    for(int i=0,len=0;i<p;++i)
    {
        at[i]=len;
        at[i+1]=len+=k[i];
        for(int j=at[i];j<at[i+1];++j)
            scanf("%lld%lld",l+j,r+j);
    }

    for(long long b=30;b>=0;--b)
    {
        long long set=1ll<<b;
        int ok=1;
        for(int i=0;i<p;++i)
        {
            if(lena[i])continue;
            int can=0;
            for(int j=at[i];j<at[i+1];++j) can+=(set<=r[j]);
            if(can==0) ok=0;
        }
        for(int i=0;i<p;++i)
        {
            int tuna=0,salmon=0;
            for(int j=at[i];j<at[i+1];++j)
            {
                salmon+=r[j]>=set;
                tuna+=r[j]>=set&&l[j]<set;
            }

            if(tuna&&(!ok||salmon>1))
            {
                lena[i]=1;
                continue;
            }

            for(int j=at[i];j<at[i+1];++j)
                if(r[j]>=set)
                {
                    r[j]-=set;
                    l[j]-=set;
                }
        }

        if(ok)
            z|=set;

        //printf(" After bit %d\n",b); for(int j=0;j<n;++j)printf(" [%lld %lld]\n",l[j],r[j]);
    }
    printf("%lld",z);
}

Compilation message (stderr)

bitwise.c: In function 'main':
bitwise.c:8:5: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
    8 |     scanf("%d%d",&n,&p);
      |     ^~~~~~~~~~~~~~~~~~~
bitwise.c:10:9: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   10 |         scanf("%d",k+i);
      |         ^~~~~~~~~~~~~~~
bitwise.c:16:13: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   16 |             scanf("%lld%lld",l+j,r+j);
      |             ^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 100 / 100