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HDU - 1166 敌兵布阵 (线段树---点修改)

题意:

1、Add i j,i和j为正整数,表示第i个营地增加j个人(j不超过30) 
2、Sub i j ,i和j为正整数,表示第i个营地减少j个人(j不超过30); 
3、Query i j ,i和j为正整数,i<=j,表示询问第i到第j个营地的总人数; 
4、End 表示结束,这条命令在每组数据最后出现。

#include<cstdio>#include<cstring>#include<cstdlib>#include<cctype>#include<cmath>#include<iostream>#include<sstream>#include<iterator>#include<algorithm>#include<string>#include<vector>#include<set>#include<map>#include<stack>#include<deque>#include<queue>#include<list>#define lowbit(x) (x & (-x))const double eps = 1e-8;inline int dcmp(double a, double b){    if(fabs(a - b) < eps) return 0;    return a > b ? 1 : -1;}typedef long long LL;typedef unsigned long long ULL;const int INT_INF = 0x3f3f3f3f;const int INT_M_INF = 0x7f7f7f7f;const LL LL_INF = 0x3f3f3f3f3f3f3f3f;const LL LL_M_INF = 0x7f7f7f7f7f7f7f7f;const int dr[] = {0, 0, -1, 1, -1, -1, 1, 1};const int dc[] = {-1, 1, 0, 0, -1, 1, -1, 1};const int MOD = 1e9 + 7;const double pi = acos(-1.0);const int MAXN = 50000 + 10;const int MAXT = 10000 + 10;using namespace std;int a[MAXN];int sum[MAXN << 2];char s[10];void build(int id, int L, int R){    if(L == R){        sum[id] = a[L];    }    else{        int mid = L + (R - L) / 2;        build(id << 1, L, mid);        build(id << 1 | 1, mid + 1, R);        sum[id] = sum[id << 1] + sum[id << 1 | 1];    }}void update(int k, int id, int L, int R, int v){    if(L == R){        sum[id] += v;    }    else{        int mid = L + (R - L) / 2;        if(k <= mid) update(k, id << 1, L, mid, v);        else update(k, id << 1 | 1, mid + 1, R, v);        sum[id] = sum[id << 1] + sum[id << 1 | 1];    }}int query(int l, int r, int id, int L, int R){    if(l <= L && R <= r){        return sum[id];    }    int mid = L + (R - L) / 2;    int ans = 0;    if(l <= mid) ans += query(l, r, id << 1, L, mid);    if(r > mid) ans += query(l, r, id << 1 | 1, mid + 1, R);    return ans;}int main(){    int T;    scanf("%d", &T);    int kase = 0;    while(T--){        memset(a, 0, sizeof a);        memset(sum, 0, sizeof sum);        int N;        scanf("%d", &N);        for(int i = 1; i <= N; ++i){            scanf("%d", &a[i]);        }        build(1, 1, N);        printf("Case %d:\n", ++kase);        while(scanf("%s", s) == 1){            if(s[0] == ‘E‘) break;            int i, j;            scanf("%d%d", &i, &j);            if(s[0] == ‘A‘){                update(i, 1, 1, N, j);            }            else if(s[0] == ‘S‘){                update(i, 1, 1, N, -j);            }            else{                printf("%d\n", query(i, j, 1, 1, N));            }        }    }    return 0;}

  

HDU - 1166 敌兵布阵 (线段树---点修改)