hdu 1698 Just a Hook(线段树)

来源：互联网发布：矩阵特征分解的方法编辑：程序博客网时间：2024/05/16 09:49
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#include <cstdio>struct node{    int l,r,sum,lazy;};node segTree[400004];void Build(int t, int l, int r){    segTree[t].l = l;    segTree[t].r = r;    segTree[t].lazy = 0;    if(l == r)    {        segTree[t].sum = 1;        return ;    }    int mid = (l+r) >> 1;    Build(t<<1,l,mid);    Build(t<<1|1,mid+1,r);    segTree[t].sum = segTree[t<<1].sum + segTree[t<<1|1].sum;}void pushDown(int t){    if(segTree[t].lazy)    {        segTree[t<<1].sum = (segTree[t<<1].r - segTree[t<<1].l + 1) * segTree[t].lazy;        segTree[t<<1].lazy = segTree[t].lazy;        segTree[t<<1|1].sum = (segTree[t<<1|1].r - segTree[t<<1|1].l + 1)*segTree[t].lazy;        segTree[t<<1|1].lazy = segTree[t].lazy;        segTree[t].lazy = 0;    }}void Update(int t, int l, int r, int c){    if(segTree[t].l >= l && segTree[t].r <= r)    {        segTree[t].sum = (segTree[t].r - segTree[t].l + 1) * c;        segTree[t].lazy = c;        return ;    }    pushDown(t);    if(r >= segTree[t<<1|1].l)        Update(t<<1|1,l,r,c);    if(l <= segTree[t<<1].r)        Update(t<<1,l,r,c);    segTree[t].sum = segTree[t<<1].sum + segTree[t<<1|1].sum;}int main(){    int t,n,o;    int time = 0;    scanf("%d",&t);    while(t--)    {        ++time;        scanf("%d",&n);        Build(1,1,n);        scanf("%d",&o);        int a,b,c;        for(int i = 0; i < o; ++i)        {            scanf("%d %d %d",&a,&b,&c);            Update(1,a,b,c);        }        printf("Case %d: The total value of the hook is %d.\n",time,segTree[1].sum);    }    return 0;}
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