#include #include #include using namespace std; typedef long long LL; const int L_TYPE = 0; const int S_TYPE = 1; const int maxn = 1e6 + 10; int n; char s[maxn]; namespace __SA_IS { int a[2000100], sa[2000100], typ[2000100], c[1000100], p[2000100], sbuc[1000100], lbuc[1000100], name[1000100]; inline int islms(int *typ, int i) { return !typ[i] && (i == 1 || typ[i - 1]); } int cmp(int *s, int *typ, int p, int q) { do { if (s[p] != s[q]) return 1; p++; q++; } while (!islms(typ, p) && !islms(typ, q)); return (!islms(typ, p) || !islms(typ, q) || s[p] != s[q]); } void isort(int *s, int *sa, int *typ, int *c, int n, int m) { int i; for (lbuc[0] = sbuc[0] = c[0], i = 1; i <= m; i++) { lbuc[i] = c[i - 1] + 1; sbuc[i] = c[i]; } for (i = 1; i <= n; i++) if (sa[i] > 1 && typ[sa[i] - 1]) sa[lbuc[s[sa[i] - 1]]++] = sa[i] - 1; for (i = n; i >= 1; i--) if (sa[i] > 1 && !typ[sa[i] - 1]) sa[sbuc[s[sa[i] - 1]]--] = sa[i] - 1; } void build_sa(int *s, int *sa, int *typ, int *c, int *p, int n, int m) { int i; for (i = 0; i <= m; i++) c[i] = 0; for (i = 1; i <= n; i++) c[s[i]]++; for (i = 1; i <= m; i++) c[i] += c[i - 1]; typ[n] = 0; for (i = n - 1; i >= 1; i--) if (s[i] < s[i + 1]) typ[i] = 0; else if (s[i] > s[i + 1]) typ[i] = 1; else typ[i] = typ[i + 1]; int cnt = 0; for (i = 1; i <= n; i++) if (!typ[i] && (i == 1 || typ[i - 1])) p[++cnt] = i; for (i = 1; i <= n; i++) sa[i] = 0; for (i = 0; i <= m; i++) sbuc[i] = c[i]; for (i = 1; i <= cnt; i++) sa[sbuc[s[p[i]]]--] = p[i]; isort(s, sa, typ, c, n, m); int last = 0, t = -1, x; for (i = 1; i <= n; i++) { x = sa[i]; if (!typ[x] && (x == 1 || typ[x - 1])) { if (!last || cmp(s, typ, x, last)) name[x] = ++t; else name[x] = t; last = x; } } for (i = 1; i <= cnt; i++) s[n + i] = name[p[i]]; if (t < cnt - 1) build_sa(s + n, sa + n, typ + n, c + m + 1, p + n, cnt, t); else for (i = 1; i <= cnt; i++) sa[n + s[n + i] + 1] = i; for (i = 0; i <= m; i++) sbuc[i] = c[i]; for (i = 1; i <= n; i++) sa[i] = 0; for (i = cnt; i >= 1; i--) sa[sbuc[s[p[sa[n + i]]]]--] = p[sa[n + i]]; isort(s, sa, typ, c, n, m); } } // namespace __SA_IS void SA_IS(char *s, int n, int *sa, int *rk) { using namespace __SA_IS; for (int i = 1; i <= n; i++) a[i] = s[i]; a[++n] = 0; build_sa(a, sa, typ, c, p, n, 256); n--; for (int i = 1; i <= n; i++) sa[i] = sa[i + 1]; for (int i = 1; i <= n; i++) rk[sa[i]] = i; } void computeHeight(char *s, int n, int *sa, int *rk, int *height) { int k = 0; for (int i = 1; i <= n; i++) { if (rk[i] == 1) { height[rk[i]] = 0; continue; } if (k > 0) { k--; } int j = sa[rk[i] - 1]; while (i + k <= n && j + k <= n && s[i + k] == s[j + k]) { k++; } height[rk[i]] = k; } } LL GetPairMin(int *height, int n) { int *index_stack = 1 + new int[n + 10](); index_stack[-1] = 0; int s_cnt = 0; LL res = 0, cur = 0; index_stack[s_cnt++] = 1; for (int i = 2; i <= n; i++) { while (s_cnt > 0 && height[index_stack[s_cnt - 1]] >= height[i]) { s_cnt--; cur -= (index_stack[s_cnt] - index_stack[s_cnt - 1]) * (LL)height[index_stack[s_cnt]]; } index_stack[s_cnt++] = i; cur += (index_stack[s_cnt - 1] - index_stack[s_cnt - 2]) * (LL)height[i]; res += cur; } delete[] (index_stack - 1); return res; } LL calc(char *s, int n) { int *sa = new int[n << 4](); int *rk = new int[n << 4](); int *height = new int[n << 4](); SA_IS(s, n, sa, rk); computeHeight(s, n, sa, rk, height); LL res = 0; for (int i = 1; i <= n; i++) res += n + 1 - sa[i] - height[i]; delete[] sa; delete[] rk; delete[] height; return res; } int main() { #ifdef local freopen("pro.in", "r", stdin); #endif scanf("%d%s", &n, s + 1); LL res = calc(s, n); printf("%lld\n", res); return 0; }