hdu 5316 Magician 线段树
2015 Multi-University Training Contest 3 1001
1 #include "bits/stdc++.h" 2 using namespace std; 3 #define M 100010 4 #define lson l,m,rt<<1 5 #define rson m+1,r,rt<<1|1 6 7 int T, n, m; 8 int ans[M]; 9 struct Node 10 { 11 int l, r; 12 long long sum11, sum12, sum21, sum22; 13 }node[M<<2], query_node; 14 const long long INF = 100000000000000 + 1; 15 16 bool First; 17 18 inline void PushPlus(int rt) 19 { 20 node[rt].sum11 = max(node[rt<<1].sum11 + node[rt<<1|1].sum21, node[rt<<1].sum12 + node[rt<<1|1].sum11); 21 node[rt].sum12 = max(node[rt<<1].sum11 + node[rt<<1|1].sum22, node[rt<<1].sum12 + node[rt<<1|1].sum12); 22 node[rt].sum21 = max(node[rt<<1].sum21 + node[rt<<1|1].sum21, node[rt<<1].sum22 + node[rt<<1|1].sum11); 23 node[rt].sum22 = max(node[rt<<1].sum21 + node[rt<<1|1].sum22, node[rt<<1].sum22 + node[rt<<1|1].sum12); 24 25 node[rt].sum11 = max(node[rt].sum11, node[rt<<1|1].sum11); 26 node[rt].sum12 = max(node[rt].sum12, node[rt<<1|1].sum12); 27 node[rt].sum21 = max(node[rt].sum21, node[rt<<1|1].sum21); 28 node[rt].sum22 = max(node[rt].sum22, node[rt<<1|1].sum22); 29 30 node[rt].sum11 = max(node[rt].sum11, node[rt<<1].sum11); 31 node[rt].sum12 = max(node[rt].sum12, node[rt<<1].sum12); 32 node[rt].sum21 = max(node[rt].sum21, node[rt<<1].sum21); 33 node[rt].sum22 = max(node[rt].sum22, node[rt<<1].sum22); 34 } 35 36 37 void Merge_Node(Node &newNode, Node lNode, Node rNode) 38 { 39 newNode.sum11 = max(lNode.sum11 + rNode.sum21, lNode.sum12 + rNode.sum11); 40 newNode.sum12 = max(lNode.sum11 + rNode.sum22, lNode.sum12 + rNode.sum12); 41 newNode.sum21 = max(lNode.sum21 + rNode.sum21, lNode.sum22 + rNode.sum11); 42 newNode.sum22 = max(lNode.sum21 + rNode.sum22, lNode.sum22 + rNode.sum12); 43 44 newNode.sum11 = max(newNode.sum11, rNode.sum11); 45 newNode.sum12 = max(newNode.sum12, rNode.sum12); 46 newNode.sum21 = max(newNode.sum21, rNode.sum21); 47 newNode.sum22 = max(newNode.sum22, rNode.sum22); 48 49 newNode.sum11 = max(newNode.sum11, lNode.sum11); 50 newNode.sum12 = max(newNode.sum12, lNode.sum12); 51 newNode.sum21 = max(newNode.sum21, lNode.sum21); 52 newNode.sum22 = max(newNode.sum22, lNode.sum22); 53 } 54 55 void Build(int l, int r, int rt) 56 { 57 if(l == r) { 58 scanf("%d", &ans[l]); 59 node[rt].sum11 = node[rt].sum12 = node[rt].sum21 = node[rt].sum22 = -INF; 60 if(l & 1) { 61 node[rt].sum11 = ans[l]; 62 } 63 else { 64 node[rt].sum22 = ans[l]; 65 } 66 // printf("l == %d r == %d sum11 == %lld sum12 == %lld sum21 == %lld sum22 == %lld\n", l, r, node[rt].sum11, node[rt].sum12, node[rt].sum21, node[rt].sum22); 67 return ; 68 } 69 int m = ( l + r )>>1; 70 Build(lson); 71 Build(rson); 72 PushPlus(rt); 73 // printf("l == %d r == %d sum11 == %lld sum12 == %lld sum21 == %lld sum22 == %lld\n", l, r, node[rt].sum11, node[rt].sum12, node[rt].sum21, node[rt].sum22); 74 } 75 76 void Update(int p, int newVal, int l, int r, int rt) 77 { 78 if(l == r) { 79 if(l & 1) { 80 node[rt].sum11 = newVal; 81 } 82 else { 83 node[rt].sum22 = newVal; 84 } 85 return ; 86 } 87 int m = (l + r) >> 1; 88 if(p <= m) 89 Update(p, newVal, lson); 90 else 91 Update(p, newVal, rson); 92 PushPlus(rt); 93 } 94 95 void Query(int L,int R,int l,int r,int rt) 96 { 97 if(L <= l && r <= R) { 98 // if(First) { 99 // First = 0; 100 // query_node = node[rt]; 101 // } 102 // else { 103 Merge_Node(query_node, query_node, node[rt]); 104 // } 105 return ; 106 } 107 int m = (l + r) >> 1; 108 if(L <= m) 109 Query(L, R, lson); 110 if(R > m) 111 Query(L, R, rson); 112 } 113 114 115 int main() 116 { 117 int i, cmd, L, R, POS, VAL; 118 scanf("%d", &T); 119 while(T--) { 120 scanf("%d%d", &n, &m); 121 Build(1, n, 1); 122 for(i = 1; i <= m; ++i) { 123 scanf("%d", &cmd); 124 if(cmd == 0) { 125 scanf("%d%d", &L, &R); 126 // First = 1; 127 query_node.sum11 = query_node.sum12 = query_node.sum21 = query_node.sum22 = -INF; 128 Query(L, R, 1, n, 1); 129 printf("%lld\n", max( max(query_node.sum11, query_node.sum12), max(query_node.sum21, query_node.sum22) )); 130 } 131 else { 132 scanf("%d%d", &POS, &VAL); 133 Update(POS, VAL, 1, n, 1); 134 } 135 } 136 } 137 }
