CF_402B 想法题

题目链接：http://codeforces.com/problemset/problem/402/B

/**算法分析：
    题意太大意，positive没注意这个问题
    考察等差数列，由An=A1+(n-1)*k,k已知，能够求出A1，找出最大的A1的个数就可以了
*/
#include<bits/stdc++.h>

#define MAXN 1050
#define PI acos(-1.0)
#define REP(i,n) for(int i=0; i<n; i++)
#define FOR(i,s,t) for(int i=s; i<=t; i++)
#define show(x) { cerr<<">>>"<<#x<<" = "<<x<<endl; }
#define showtwo(x,y) { cerr<<">>>"<<#x<<"="<<x<<"  "<<#y<<" = "<<y<<endl; }
using namespace std;

int main()
{
    //freopen("E:\\acm\\input.txt","r",stdin);
    int n,k; cin>>n>>k;
    int a[MAXN];
    map<int,int> G;

    int ans=0,mx = 0;
    FOR(i,1,n)
    {
        cin>>a[i];
        int tmp = a[i] - (i-1)*k;
        if(tmp <= 0) continue;
        G[tmp]++;
        if(ans < G[tmp]) ans = G[tmp], mx = tmp;
    }
    cout<<n - ans<<endl;
    FOR(i,1,n)
    {
        int tmp = mx + (i-1)*k;
        if(tmp > a[i])      printf("+ %d %d\n",i,tmp-a[i]);
        else if(tmp < a[i]) printf("- %d %d\n",i,a[i]-tmp);
    }
}