題目連結

#include "stdio.h"
const int maxn = 100050;
int n,x,y,z;
struct Node
{
    int val;
}tree[maxn*4];

void pushup( int t )
{
    tree[t].val = tree[t*2].val + tree[t*2+1].val;
}
void pushdown( int t )
{
    tree[t*2].val = tree[t*2+1].val = tree[t].val;
}

void buildtree( int ld,int rd,int t )
{
    tree[t].val = 1;
    if( ld == rd )
    {    
        return;
    }
    int mid = ( ld+rd )/2;
    buildtree( ld,mid,t*2 );
    buildtree( mid+1,rd,t*2+1 );
}

void updata( int ld,int rd,int t )
{
    if( x<=ld && rd<=y )
    {
        tree[t].val = z;
        return;
    }
    if( tree[t].val )
    {
        pushdown( t );
        tree[t].val = 0;
    }
    int mid = ( ld + rd )/2;
    if( x<=mid )    updata( ld,mid,t*2 );
    if( y>mid )    updata( mid+1,rd,t*2+1);
        
}

int sum( int ld,int rd ,int t )
{
    if( tree[t].val )
        return ( rd - ld + 1 )*tree[t].val;
    int mid = ( ld + rd )/2;
    return sum( ld,mid,t*2 ) + sum( mid+1,rd,t*2+1 );
} 

int main()
{
    int i,j,t,cas=1,q;
    scanf("%d",&t);
    while( t-- )
    {
        scanf("%d%d",&n,&q);
        buildtree( 1,n,1 );
        for( i=1; i<=q; i++ )
        {
            scanf("%d%d%d",&x,&y,&z);
            updata( 1,n,1 );
        }
        printf( "Case %d: The total value of the hook is %d.\n",cas++,sum( 1,n ,1) );
    }
    return 0;
}