题解 | #密码截取#

#include <iostream>
#include <cstring>
#include <cstdio>



char nums1[2500];

int fexpand(int lo,int hi,int nsize1);

int main()
{
    
    while(scanf("%s",nums1)!=EOF)
    {
        int nsize1=strlen(nums1);
        //printf("%d\n",nsize1);
        int maxv=1,keeplo,keephi;
        for(int i=0;i<nsize1;++i)
        {
            int a1=fexpand(i,i,nsize1);
            if(maxv<a1)
            {
                maxv=a1;
                // keeplo=i-(maxv-1)/2;
                // keephi=i+(maxv-1)/2;
            }
            int a2=fexpand(i,i+1,nsize1);
            if(maxv<a2)
            {
                maxv=a2;
                // keeplo=i-(maxv-2)/2;
                // keephi=i+1+(maxv-2)/2;
            }

            
        }
        printf("%d\n",maxv);

    }
    
}

int fexpand(int lo,int hi,int nsize1)
{

    while(0<=lo && hi<nsize1 && nums1[lo]==nums1[hi])
    {
        --lo;
        ++hi;
    }
    return hi-lo-1;
}