线段树（四）——两个标记（add和set）

  1 #include<bits/stdc++.h>
  2 using namespace std;
  3 
  4 const int INF = 0x3f3f3f3f;
  5 const int maxn = 100000 + 10;
  6 const int maxnode = maxn << 2;
  7 int sumv[maxnode], minv[maxnode], maxv[maxnode], setv[maxnode], addv[maxnode];
  8 int n, a[maxn];
  9 
 10 // 维护信息
 11 void maintain(int o, int L, int R) {
 12     int lc = o*2, rc = o*2+1;
 13     if(R > L) {
 14       sumv[o] = sumv[lc] + sumv[rc];
 15       minv[o] = min(minv[lc], minv[rc]);
 16       maxv[o] = max(maxv[lc], maxv[rc]);
 17     }
 18     if(setv[o] >= 0) { minv[o] = maxv[o] = setv[o]; sumv[o] = setv[o] * (R-L+1); }
 19     if(addv[o]) { minv[o] += addv[o]; maxv[o] += addv[o]; sumv[o] += addv[o] * (R-L+1); }
 20 }
 21 
 22 // 标记传递
 23 void pushdown(int o) {
 24     int lc = o*2, rc = o*2+1;
 25     if(setv[o] >= 0) {
 26       setv[lc] = setv[rc] = setv[o];
 27       addv[lc] = addv[rc] = 0;
 28       setv[o] = -1; // 清除本结点标记
 29     }
 30     if(addv[o]) {
 31       addv[lc] += addv[o];
 32       addv[rc] += addv[o];
 33       addv[o] = 0; // 清除本结点标记
 34     }
 35 }
 36 
 37 int op,cl,cr,v;
 38 void update(int o, int L, int R) {
 39     int lc = o*2, rc = o*2+1;
 40     if(cl <= L && cr >= R) { // 标记修改
 41       if(op == 2) addv[o] += v;
 42       else { setv[o] = v; addv[o] = 0; }
 43     } else {
 44       pushdown(o);
 45       int M = L + (R-L)/2;
 46       if(cl <= M) update(lc, L, M); else maintain(lc, L, M);
 47       if(cr > M) update(rc, M+1, R); else maintain(rc, M+1, R);
 48     }
 49     maintain(o, L, R);
 50 }
 51 
 52 int ql, qr;
 53 void query(int o, int L, int R, int& ssum, int& smin, int &smax) {
 54     int lc = o*2, rc = o*2+1;
 55     maintain(o, L, R); // 处理被pushdown下来的标记
 56     if(ql <= L && qr >= R) {
 57       ssum = sumv[o];
 58       smin = minv[o];
 59       smax = maxv[o];
 60     } else {
 61       pushdown(o);
 62       int M = L + (R-L)/2;
 63       int lsum = 0, lmin = INF, lmax = -INF;
 64       int rsum = 0, rmin = INF, rmax = -INF;
 65       if(ql <= M) query(lc, L, M, lsum, lmin, lmax); else maintain(lc, L, M);
 66       if(qr > M) query(rc, M+1, R, rsum, rmin, rmax); else maintain(rc, M+1, R);
 67       ssum = lsum + rsum;
 68       smin = min(lmin, rmin);
 69       smax = max(lmax, rmax);
 70     }
 71 }
 72 
 73 void print_debug(int o, int L, int R)
 74 {
 75     printf("o:%d  L:%d  R:%d  setv:%d  addv:%d  minv:%d\n", o, L, R, setv[o], addv[o], minv[o]);
 76     if(R > L)
 77     {
 78         int M = L + (R - L) / 2;
 79         print_debug(2*o, L, M);
 80         print_debug(2*o+1, M+1, R);
 81     }
 82 }
 83 
 84 int main()
 85 {
 86     memset(setv, 0, sizeof(setv));
 87 
 88     printf("数组元素个数：");
 89     scanf("%d", &n);
 90     printf("数组元素：");
 91     for(int i = 1; i <= n;i++)
 92     {
 93          scanf("%d", &a[i]);
 94          cl = cr = i; v = a[i]; op=2;
 95          update(1, 1, n);
 96     }
 97 
 98     printf("1代表查询，2代表增加，3代表设置\n");
 99     printf("选择：");
100     int chose;
101     while(scanf("%d", &chose) == 1)
102     {
103         if(chose == 1)
104         {
105             printf("查询的左右区间：");
106             scanf("%d%d", &ql, &qr);
107             int ssum, smin, smax;
108             query(1, 1, n, ssum, smin, smax);
109             printf("最小值：%d\n", smin);
110             print_debug(1, 1, n);
111         }
112         else if(chose == 2)
113         {
114             printf("左右区间和增加值：");
115             scanf("%d%d%d", &cl, &cr, &v);
116             op = 2;
117             update(1, 1, n);
118             print_debug(1, 1, n);
119         }
120         else
121         {
122             printf("左右区间和设置值：");
123             scanf("%d%d%d", &cl, &cr, &v);
124             op = 3;
125             update(1, 1, n);
126             print_debug(1, 1, n);
127         }
128         printf("选择：");
129     }
130 
131     return 0;
132 }