2777 Count Color 解题报告

 #include<memory.h> #include<stdio.h> #define L 100010 #define C 35 #define NoCol 0 #define MulCol -1 struct TNode { int left,right; int col; }; TNode tree[L*10]; bool col[35]; //创建线段树 void construct(int pos,int l,int r) { tree[pos].left = l; tree[pos].right = r; tree[pos].col = NoCol; if(l == r) return; construct(2*pos,l,(l+r)>>1); construct(2*pos+1,((l+r)>>1)+1,r); } //插入节点 void insert(int pos,int l,int r,int c) { if(tree[pos].col == c) return ; if(l==tree[pos].left && r==tree[pos].right) { tree[pos].col = c; return ; } if(tree[pos].col != MulCol) { tree[pos*2].col = tree[pos].col; tree[pos*2+1].col = tree[pos].col; } int mid = (tree[pos].left+tree[pos].right)/2; tree[pos].col = MulCol; if(r <= mid) { insert(pos*2,l,r,c); return ; } if(l > mid) { insert(pos*2+1,l,r,c); return; } insert(pos*2,l,mid,c); insert(pos*2+1,mid+1,r,c); return; } //对颜色进行统计 void calculate(int pos,int l,int r) { if(tree[pos].col != MulCol) { col[tree[pos].col] = true; return ; } int mid = (tree[pos].left + tree[pos].right)>>1; if(r <= mid) { calculate(pos*2,l,r); return; } if( l > mid) { calculate(pos*2+1,l,r); return ; } calculate(pos*2,l,mid); calculate(pos*2+1,mid+1,r); return; } int main() { int l,t,o; int a,b,c; int tmp,res; char op; scanf("%d%d%d/n",&l,&t,&o); construct(1,1,L); for(int i = 0; i < o; i++) { scanf("%c%d%d",&op,&a,&b); if(a > b) { tmp = b; b = a; a = tmp; } if(op == 'C') { scanf("%d/n",&c); insert(1,a,b,c-1); } else { getchar(); memset(col,NoCol,sizeof(col)); calculate(1,a,b); res = 0; for(int i = 0; i < 31; i++) if(col[i]) res++; printf("%d/n",res); } } return 0; } // // suikay 2777 Accepted 3388K 391MS G++ 1806B //

 

更快的方法看这： http://blog.youkuaiyun.com/xiaofengsheng/archive/2009/03/03/3953265.aspx