思路:单调栈加后缀数组。有点绕(尼玛又发现了后缀数组板子的bugQAQ),如果全是 0 g.s 的初始化也为0,求h数组就凉了
//本质不同的子串个数
#include <bits/stdc++.h>
using namespace std;
typedef long long LL;
typedef int lint;
const lint maxn = 2000000 + 10;
typedef int lint;
struct suffix{
lint c[maxn],sa[maxn],t1[maxn],t2[maxn],m,n,h[maxn],height[maxn],rk[maxn],s[maxn];
void Build_SA(lint len){
m = 0;
lint* x = t1,*y = t2;
n = len;
for( lint i = 0;i < n;i++ ) m = max( m,s[i] );
for( lint i = 0;i <= m;i++ ) c[i] = 0;
for( lint i = 0;i < n;i++ ) c[ x[i] = s[i] ]++;
for( lint i = 1;i <= m;i++ ) c[i] += c[i-1];
for( lint i = n-1;i >= 0;i-- ) {
sa[ --c[ x[i] ] ] = i;
}
for( lint k = 1;k < n;k <<= 1 ){
lint cnt = 0;
for( lint i = n - 1;i >= n-k;i-- ) y[cnt++] = i;
for( lint i = 0;i < n;i++ ) if( sa[i] >= k ) y[cnt++] = sa[i]-k;
for( lint i = 0;i <= m;i++ ) c[i] = 0;
for( lint i = 0;i < n;i++ ) c[ x[i] ]++;
for( lint i = 1;i <= m;i++ ) c[i] += c[i-1];
for( lint i = cnt-1;i >= 0;i-- ) sa[ --c[ x[ y[i] ] ] ] = y[i];
swap( x,y );
lint num = 0;
x[ sa[0] ] = 0;
for( lint i = 1;i < n;i++ ){
if( y[ sa[i-1] ] != y[ sa[i] ] || y[ sa[i-1]+k ] != y[ sa[i]+k ] ){
x[ sa[i] ] = ++num;
}else{
x[ sa[i] ] = num;
}
}
if( num == n-1 ) return;
m = num;
}
}
void getheight(){
for( lint i = 0;i < n;i++ ){
rk[ sa[i] ] = i;
}
lint cnt = 1;
h[ sa[0] ] = 0;
height[ 0 ] = 0;
for( lint i = 0;i < n;i++ ){
if(cnt)cnt--;
while( rk[i] >= 1 && sa[rk[i]-1]+cnt < n && i + cnt < n && s[ sa[rk[i]-1]+cnt ] == s[ i+cnt ] ) cnt++;
h[ i ] = cnt;
height[ rk[i] ] = cnt;
}
//cout << "debug" << endl;
}
}g;
lint a[maxn];
vector<lint> ve;
void discrete(){
sort( ve.begin(),ve.end() );
auto p = unique( ve.begin(),ve.end() );
ve.erase( p,ve.end() );
}
lint Q( lint x ){
return lower_bound( ve.begin(),ve.end(),x ) - ve.begin();
}
lint st[maxn],top,n;
LL sum[maxn],ans;
void solve(){
for( lint i = n-1;i >= 0;i-- ){
while( top && a[ -st[top-1] ] < a[i] ) {
//sum -= a[ -st[top-1] ]*( );
top--;
}
st[top++] = -i;
sum[top-1] = ((top != 1)? (LL)a[i]*( st[top-1]-st[top-2] ) : (LL)a[i]*( n - i )) + sum[top-2] ;
lint len = g.h[i];
lint pos = lower_bound( st,st+top,-( i+len- 1 ) ) -st;
pos--;
if( pos == -1 ){
ans += (LL)a[ -st[pos+1] ] *( n - (i+len) );
}else{
ans += sum[pos]+(LL)a[-st[pos+1] ]*( -st[pos]-(i+len-1)-1 );
}
}
}
int main()
{
lint T;
scanf("%d",&T);
while( T-- ){
ve.clear();top = 0;ans = 0;
scanf("%d",&n);
for( lint i = 0;i < n;i++ ){
scanf("%d",&a[i]);
ve.push_back( a[i] );
}
discrete();
for( lint i = 0;i < n;i++ ){
g.s[i] = Q( a[i] );
}
g.Build_SA(n);
g.getheight();
solve();
printf("%lld\n",ans);
}
}
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