HDU5475(线段树)
An easy problem
Time Limit: 8000/5000 MS (Java/Others) Memory Limit: 65536/65536 K (Java/Others)
Total Submission(s): 1553 Accepted Submission(s): 697
Problem Description
One day, a useless calculator was being built by Kuros. Let's assume that number X is showed on the screen of calculator. At first, X = 1. This calculator only supports two types of operation.
1. multiply X with a number.
2. divide X with a number which was multiplied before.
After each operation, please output the number X modulo M.
1. multiply X with a number.
2. divide X with a number which was multiplied before.
After each operation, please output the number X modulo M.
Input
The first line is an integer T(1≤T≤10), indicating the number of test cases.
For each test case, the first line are two integers Q and M. Q is the number of operations and M is described above. (1≤Q≤105,1≤M≤109)
The next Q lines, each line starts with an integer x indicating the type of operation.
if x is 1, an integer y is given, indicating the number to multiply. (0<y≤109)
if x is 2, an integer n is given. The calculator will divide the number which is multiplied in the nth operation. (the nth operation must be a type 1 operation.)
It's guaranteed that in type 2 operation, there won't be two same n.
For each test case, the first line are two integers Q and M. Q is the number of operations and M is described above. (1≤Q≤105,1≤M≤109)
The next Q lines, each line starts with an integer x indicating the type of operation.
if x is 1, an integer y is given, indicating the number to multiply. (0<y≤109)
if x is 2, an integer n is given. The calculator will divide the number which is multiplied in the nth operation. (the nth operation must be a type 1 operation.)
It's guaranteed that in type 2 operation, there won't be two same n.
Output
For each test case, the first line, please output "Case #x:" and x is the id of the test cases starting from 1.
Then Q lines follow, each line please output an answer showed by the calculator.
Then Q lines follow, each line please output an answer showed by the calculator.
Sample Input
1
10 1000000000
1 2
2 1
1 2
1 10
2 3
2 4
1 6
1 7
1 12
2 7
Sample Output
Case #1:
2
1
2
20
10
1
6
42
504
84
思路:该题用long long 类型运算会溢出,结果WA。用高精度会TLE。线段树思路:第i个叶子结点维护的是第i个操作.若为乘运算则将结点的值修改为乘数,若为除运算则将结点的值修改为1.父结点维护左右子结点之积。每次输出结果为根节点的值。
#include <cstdio> #include <algorithm> using namespace std; const int MAXN=100005; typedef long long ll; struct Node{ ll val; int l,r; }a[MAXN*3]; int n,mod; void build(int rt,int l,int r) { a[rt].l=l; a[rt].r=r; a[rt].val=1; if(l==r) { return ; } int mid=(l+r)>>1; build(rt<<1,l,mid); build((rt<<1)|1,mid+1,r); } void update(int rt,int pos,int val) { if(a[rt].l==pos&&a[rt].r==pos) { a[rt].val=val%mod; return ; } int mid=(a[rt].l+a[rt].r)>>1; if(pos<=mid) { update(rt<<1,pos,val); } else { update((rt<<1)|1,pos,val); } a[rt].val=(a[rt<<1].val*a[(rt<<1)|1].val)%mod; } int main() { int T; scanf("%d",&T); for(int cas=1;cas<=T;cas++) { scanf("%d%d",&n,&mod); build(1,1,n); printf("Case #%d:\n",cas); for(int i=1;i<=n;i++) { int type,val; scanf("%d%d",&type,&val); if(type==1) { update(1,i,val); } else { update(1,val,1); } printf("%lld\n",a[1].val); } } return 0; }