【POJ】3468 A Simple Problem with Integers
线段树。段区间，终于完全自己A掉的。
1 #include <cstdio> 2 #include <cstring> 3 4 #define MAXN 100005 5 #define lson l, mid, rt<<1 6 #define rson mid+1, r, rt<<1|1 7 8 __int64 sums[MAXN<<2]; 9 __int64 adds[MAXN<<2]; 10 11 inline void PushUP(int rt) { 12 sums[rt] = sums[rt<<1] + sums[rt<<1|1]; 13 } 14 15 inline void PushDown(int len, int rt) { 16 if ( adds[rt] ) { 17 adds[rt<<1] += adds[rt]; 18 adds[rt<<1|1] += adds[rt]; 19 sums[rt<<1|1] += adds[rt] * (len>>1); 20 sums[rt<<1] += adds[rt] * (len-(len>>1)); 21 adds[rt] = 0; 22 } 23 } 24 25 void build(int l, int r, int rt) { 26 int mid; 27 adds[rt] = 0; 28 if (l == r) { 29 scanf("%I64d", &sums[rt]); 30 return ; 31 } 32 mid = (l+r)>>1; 33 build(lson); 34 build(rson); 35 PushUP(rt); 36 } 37 38 void update(int ll, int rr, int c, int l, int r, int rt) { 39 int mid; 40 if (ll<=l && rr>=r) { 41 sums[rt] += c*(r-l+1); 42 adds[rt] += c; 43 return ; 44 } 45 PushDown(r-l+1, rt); 46 mid = (l+r)>>1; 47 if (ll <= mid) 48 update(ll, rr, c, lson); 49 if (rr > mid) 50 update(ll, rr, c, rson); 51 PushUP(rt); 52 } 53 54 __int64 query(int ll, int rr, int l, int r, int rt) { 55 int mid; 56 __int64 ret = 0; 57 if (ll<=l && rr>=r) 58 return sums[rt]; 59 PushDown(r-l+1, rt); 60 mid = (l+r)>>1; 61 if (ll <= mid) 62 ret += query(ll, rr, lson); 63 if (rr > mid) 64 ret += query(ll, rr, rson); 65 //PushUP(rt); 66 return ret; 67 } 68 69 int main() { 70 int n, m; 71 int x, y, c; 72 char cmd[3]; 73 74 while (scanf("%d %d", &n, &m) != EOF) { 75 build(1, n, 1); 76 77 while (m--) { 78 scanf("%s %d %d", cmd, &x, &y); 79 if (cmd[0] == 'C') { 80 scanf("%d", &c); 81 update(x,y,c,1,n,1); 82 } else { 83 printf("%I64d\n", query(x,y,1,n,1)); 84 } 85 } 86 } 87 88 return 0; 89 }
