Segment Tree POJ 2991

All we have to do is sum up these vectors, and the final point is the end point, so we just maintain the bounds of the vector and we can. For the second problem, we can use an array degree[i] to represent the i-1 vector and the current angle of the first vector, so that there is the current state, each read into the operation will be convenient to get the equivalent of the rotation of how many angles of operation, and then update the degree[i] can. And each time we read an operation that affects only one degree[] value, it does not affect the other degree[].

All in all, we want to think of each segment as a vector, and maintain the interval of these vectors, as well as the operation of adding a value to each element in the interval.

#include <stdio.h>#include<string.h>#include<algorithm>#include<math.h>using namespacestd;#defineMAXN 10010Const DoublePi =acos (-1.0);intz[maxn],deg[maxn],re[maxn<<3];structnode{intL,r; Doublex, y;} X[MAXN<<3];DoubleGetrad (inta) {    returna*pi/ the;}voidBuild (intLintRinta) {X[A].L=l; X[A].R=R; x[a].x=0; X[a].y=z[r]-z[l-1]; Re[a]=0; if(l==R)return ; intMid= (l+r) >>1; Build (L,mid,a<<1); Build (Mid+1,r,a<<1|1);}voidRotate (Double&AMP;DX,Double&dy,Doublerad) {    Doublex=dx,y=dy; DX=x*cos (RAD)-y*sin (RAD); Dy=x*sin (RAD) +y*cos (RAD);}voidPush_down (inta) {    DoubleRad=Getrad (Re[a]); intls=a<<1,rs=a<<1|1; if(Re[a]) {Re[ls]+=Re[a]; RE[RS]+=Re[a];        Rotate (X[ls].x,x[ls].y,rad);        Rotate (X[rs].x,x[rs].y,rad); Re[a]=0; }}voidPUSH_UP (inta) {x[a].x=x[a<<1].x+x[a<<1|1].x; X[a].y=x[a<<1].y+x[a<<1|1].y;}voidUpdateintLintRintA1,intWinta) {    DoubleRad=Getrad (W); if(l==r) {Rotate (X[a].x,x[a].y,rad); return ;    } push_down (a); intMid= (l+r) >>1; if(mid<A1) Update (Mid+1,r,a1,w,a<<1|1); Else{update (L,mid,a1,w,a<<1); Rotate (X[a<<1|1].x,x[a<<1|1].y,rad); Re[a<<1|1]+=W; } push_up (a);}intMain () {intN,m,ca=1;  while(SCANF ("%d%d", &n,&m)! =EOF) {        if(ca!=1) printf ("\ n"); CA++;  for(intI=1; i<=n;i++) {scanf ("%d",&Z[i]); Z[i]=z[i-1]+Z[i]; } memset (deg,0,sizeof(deg)); Build (1N1);  for(intI=1; i<=m;i++)        {            intS,a; scanf ("%d%d",&s,&a); S++; A=a- the; intdelta=a-Deg[s]; Deg[s]=A; Update (1, N,s,delta,1); printf ("%.2LF%.2lf\n", x[1].x,x[1].y); }    }    return 0;}

Segment Tree POJ 2991