H CodeForces 159C String Manipulation 1.0

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该题跟前面的POJ 2886蛮像的·~给出了相对位置·~处理处绝对位置就好了·~

因为空间问题。。所以建了26个树状数组，然后二分找答案即可

/*===============*\| *** *** *** *** ||  *  **  *   * * || *** *** *   *** ||    ID: ZERO     ||    LANG: C++    |\*===============*/#include <vector>#include <map>#include <set>#include <deque>#include <stack>#include <bitset>#include <algorithm>#include <sstream>#include <iostream>#include <cstdio>#include <queue>#include <cmath>#include <cstdlib>#include <cstring>#include <ctime>#include <string>#include <cassert>using namespace std;#define maxn 200001#define mod (int)(1e9+7)int tree[28][maxn];int lowbit(int x){    return x&(-x);}void add(int x,int v,int *arr){    while(x<=maxn-1){        arr[x]+=v;        x+=lowbit(x);    }}int sumit(int x,int *arr){    int sum=0;    while(x>0){        sum+=arr[x];        x-=lowbit(x);    }    return sum;}int find(int nn,int *arr,int ll,int rr){    int l,r,ans;    l=ll,r=rr;    int mid=(l+r)/2;    while(r>l+1){        mid=(l+r)/2;        ans=sumit(mid,arr);        if(ans>nn) r=mid-1;        else if(ans<nn)l=mid+1;        else r=mid;    }    if(sumit(l,arr)==nn) return l;    if(sumit(mid,arr)==nn) return mid;    return r;}char s[maxn];int main(){    int i,j,k;    while(~scanf("%d",&k)){        scanf("%s",s);        int len=strlen(s);        int n;        scanf("%d",&n);        for(i=0;i<k;i++){            for(j=0;j<len;j++){                add(i*len+j+1,1,tree[s[j]-'a']);                s[i*len+j]=s[j];            }        }        char temp[2];        int nn;        while(n--){            scanf("%d%s",&nn,temp);            int now=find(nn,tree[temp[0]-'a'],1,k*len);//二分找绝对位置            s[now-1]=0;//标记掉该点            add(now,-1,tree[temp[0]-'a']);//相应在数组中减掉该点        }        for(i=0;i<k*len;i++){            if(s[i]) printf("%c",s[i]);//未标记则输出        }        printf("\n");    }    return 0;}