Codeforces Beta Round #18 (Div. 2 only) C. Stripe prefix and

C. Stripe

Time Limit:20 Sec

Memory limit:256 MB

Topic Connection

Http://codeforces.com/problemset/problem/18/C

Descriptiononce Bob took a paper stripe of n squares (the height of the stripe is 1 square). In each square he wrote an integer number, possibly negative. He became interested in what many ways exist to cut this stripe into II pieces so and the sum of numbers from one piece I s equal to the sum of numbers from the other piece, and each piece contains positive integer amount of squares. Would you help Bob solve this problem?

Input

The first input line contains an integer n (1≤n≤105)-amount of squares in the stripe. The second line contains n space-separated numbers-they is the numbers written in the squares of the stripe. These numbers is integer and does not exceed 10000 in absolute value.

Output

Output The amount of ways to cut the stripe into and non-empty pieces so, the sum of numbers from one piece is equal t o The sum of numbers from the other piece. Don ' t forget that it's allowed to cut the stripe along the squares ' borders only.

Sample Input

9
1 5-6 7 9-16 0-2 2

Sample Output

3

HINT

Test instructions

Give you the number of N, and then say with a pair of scissors to cut this sequence, ask the left equals to the right, ask how many kinds of cut-off method

Exercises

Statistics a prefix and just fine ...

Code

//Qscqesze#include <cstdio>#include<cmath>#include<cstring>#include<ctime>#include<iostream>#include<algorithm>#include<Set>#include<vector>#include<sstream>#include<queue>#include<typeinfo>#include<fstream>#include<map>#include<stack>typedefLong Longll;using namespacestd;//freopen ("d.in", "R", stdin);//freopen ("D.out", "w", stdout);#defineSspeed ios_base::sync_with_stdio (0); Cin.tie (0)#defineMAXN 2000001#defineMoD 1000000007#defineEPS 1e-9intNum;Charch[ -];Const intinf=0x3f3f3f3f; inline ll read () {intx=0, f=1;CharCh=GetChar ();  while(ch<'0'|| Ch>'9'){if(ch=='-') f=-1; ch=GetChar ();}  while(ch>='0'&&ch<='9') {x=x*Ten+ch-'0'; ch=GetChar ();} returnx*F;}//**************************************************************************************intN;intA[MAXN];intSUM[MAXN];intMain () {intn=read ();  for(intI=1; i<=n;i++) A[i]=read (), sum[i]=a[i]+sum[i-1]; intans=0;  for(intI=1; i<=n-1; i++)    {        if(sum[i]==sum[n]-Sum[i]) ans++; } cout<<ans<<Endl;}

Codeforces Beta Round #18 (Div. 2 only) C. Stripe prefix and