OI

【线段树】忠诚

只有建树查询的最简形式，模板水水

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#include<stdio.h>
#define inf 2147483647
int tree[100005*4]={0},a[100005]={0};

int min(int a,int b){
    if(a<b)return a;
    return b;
}

void build(int rt,int st,int ed){
    if(st==ed)
      tree[rt]=a[st];
    else{
        int mid=(st+ed)/2;
        build(rt*2,st,mid);
        build(rt*2+1,mid+1,ed);
        tree[rt]=min(tree[rt*2],tree[rt*2+1]);
    }
}

int query(int rt,int nst,int ned,int qst,int qed){
    if(qst>ned||qed<nst)
      return inf;
    if(qst<=nst&&qed>=ned)
      return tree[rt];
    int mid=(nst+ned)/2;
    return min(query(rt*2,nst,mid,qst,qed),query(rt*2+1,mid+1,ned,qst,qed));
}

int main(){
    int n,m;
    int i,x,y;
    scanf("%d%d",&n,&m);
    for(i=1;i<=n;i++)
      scanf("%d",&a[i]);
    
    build(1,1,n);
    for(i=1;i<=m;i++){
        scanf("%d%d",&x,&y);
        printf("%d ",query(1,1,n,x,y));
    }
    return 0;
}