LOJ#6279. 数列分块入门 3
区间加值还是正常的操作,查找前驱的时候用lower_bound查找,然后范围所在位置的值
#include<map> #include<set> #include<ctime> #include<cmath> #include<stack> #include<queue> #include<string> #include<vector> #include<cstdio> #include<cstdlib> #include<cstring> #include<iostream> #include<algorithm> #define first fi #define second se #define lowbit(x) (x & (-x)) typedef unsigned long long int ull; typedef long long int ll; const double pi = 4.0*atan(1.0); const int inf = 0x3f3f3f3f; const int maxn = 100005; const int maxm = 100000; const int mod = 998244353; using namespace std; int n, m, tol, T; int block; int a[maxn]; int b[maxn]; int add[maxn]; int belong[maxn]; void init() { memset(a, 0, sizeof a); memset(add, 0, sizeof a); memset(belong, 0, sizeof belong); } int L(int x) { return (x-1)*block+1; } int R(int x) { return min(x*block, n); } void sor(int x) { for(int i=L(x); i<=R(x); i++) { a[i] += add[x]; b[i] = a[i]; } add[x] = 0; sort(b+L(x), b+R(x)+1); } void update(int l, int r, int c) { for(int i=l; i<=min(r, R(belong[l])); i++) a[i] += c; sor(belong[l]); if(belong[l] == belong[r]) return; if(belong[l] != belong[r]) { for(int i=L(belong[r]); i<=r; i++) a[i] += c; sor(belong[r]); } for(int i=belong[l]+1; i<belong[r]; i++) add[i] += c; } int query(int l, int r, int c) { int ans = -inf; for(int i=l; i<=min(r, R(belong[l])); i++) { if(a[i] + add[belong[i]]< c) ans = max(ans, a[i] + add[belong[i]]); } if(belong[l] != belong[r]) { for(int i=L(belong[r]); i<=r; i++) { if(a[i] + add[belong[i]] < c) ans = max(ans, a[i] + add[belong[i]]); } } for(int i=belong[l]+1; i<belong[r]; i++) { int pl = L(i); int pr = R(i); if(b[pl] + add[i] >= c) continue; int pos = lower_bound(b+L(i), b+R(i)+1, c - add[i]) - b - 1; while(b[pos] + add[i] >= c) { pos--; } ans = max(ans, b[pos] + add[i]); } return ans == -inf ? -1 : ans; } int main() { while(~scanf("%d", &n)) { init(); block = sqrt(n); int num = n / block + (n % block == 1); for(int i=1; i<=n; i++) { scanf("%d", &a[i]); belong[i] = (i-1) / block + 1; } for(int i=1; i<=num; i++) sor(i); m = n; while(m--) { int op, l, r, c; scanf("%d%d%d%d", &op, &l, &r, &c); if(op == 0) { update(l, r, c); } else { int ans = query(l, r, c); printf("%d\n", ans); } } } return 0; }