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<\/p>\n<\/p>\n#include <cstdio>\n#include <cstring>\n#include <iostream>\n#define N 1000010\n#define rep(i,l,r) for(int i=l;i<=r;i++)\n#define rrep(i,r,l) for(int i=r;i>=l;i--)\nusing namespace std;\ntypedef long long ll;\nint t1[N],t2[N],sa[N],h[N],rk[N],c[10*N],a[N],m,n;\nchar s[N];\nvoid calcsa(int n,int m){\n\tint *x = t1,*y = t2,p = 0,f = 0;\n\tmemset(c,0,4*m+40);\n\trep(i,1,n)c[x[i]=a[i]]++;\n\trep(i,1,m)c[i]+=c[i-1];\n\trrep(i,n,1)sa[c[x[i]]--]=i;\n\tfor(int i=1;i<=n&&p<=n;i*=2){\n\t\tp=0;\n\t\trep(j,n-i+1,n)y[++p]=j;\n\t\trep(j,1,n)if(sa[j]>i)y[++p]=sa[j]-i;\n\t\tmemset(c,0,4*m+40);\n\t\trep(j,1,n)c[x[y[j]]]++;\n\t\trep(j,1,m)c[j]+=c[j-1];\n\t\trrep(j,n,1)sa[c[x[y[j]]]--]=y[j];\n\t\tswap(x,y);x[sa[1]]=1;p=2;\n\t\trep(j,2,n)x[sa[j]]=y[sa[j]]==y[sa[j-1]]&&y[sa[j]+i]==y[sa[j-1]+i]?p-1:p++;\n\t\tm=p;\n\t}\n\trep(i,1,n)rk[sa[i]]=i;\n\trep(i,1,n){\n\t\tint j=sa[rk[i]-1];\n\t\tif(f)f--;while(a[i+f]==a[j+f])f++;\n\t\th[rk[i]]=f;\n\t}\n}\nint st[N],stn = 0,l[N],r[N];\nint main(){\n\tios::sync_with_stdio(false);\n\tcin.tie(0);\n cin>>s;\n int len=strlen(s);\n for(int i=0;i<len;i++)a[++n]=s[i]-' ';\n calcsa(n,10000);\n\tll ans = 0;\n\tfor(int i=1;i<=n;i++) ans+=1ll*i*(i-1)+1ll*i*(i-1)\/2;\n\th[1] = h[n+1] = -1;\n\tst[0] = 1;stn=1;\n\tfor(int i=2;i<=n;i++){\n\t\twhile(h[st[stn-1]]>h[i])stn--;\n\t\tl[i] = st[stn-1];\n\t\tst[stn] = i;\n\t\tstn++;\n\t}\n\tst[0] = n+1;stn=1;\n\tfor(int i=n;i>=2;i--){\n\t\twhile(h[st[stn-1]]>=h[i])stn--;\n\t\tr[i] = st[stn-1];\n\t\tst[stn] = i;\n\t\tstn++;\n\t}\n\tfor(int i=2;i<=n;i++)ans-=2ll*h[i]*(r[i]-i)*(i-l[i]);\n\tcout<<ans<<endl;\n\treturn 0;\n}\n<\/pre>\n