Segmented Tree 1

#include <bits/stdc++.h>
using namespace std;

int a[1000];
string b;

int tr[3*1003];

void build(int node, int l, int r){

        if(l==r){
            tr[node]=a[l];
            return;
        }

        int mid = (l+r)/2;

        build(node*2, l, mid);
        build((node*2)+1, mid+1, r);

        tr[node] = min(tr[node*2], tr[(node*2)+1]);

}

int query(int node, int s, int e, int l, int r){

        if(s>=l && e<=r){
            return tr[node];
        }

        int mid = (s+e)/2;
        if(l>mid){
            return query((node*2)+1, mid+1, e, l, r);
        }

        else if(r<=mid){
            return query(node*2, s, mid, l, r);
        }

        else{
            return min(query(node*2, s, mid, l, mid), query((node*2)+1, mid+1, e, mid+1, r));
        }

}

void update(int node, int s, int e, int ind, int val){

        if(s==e){
            a[ind] = val;//not necessary
            tr[node]=val;
            return;
        }

        int mid = (s+e)/2;

        if(ind<=mid){
            update(node*2, s, mid, ind, val);
        }

        else{
            update((node*2)+1, mid+1, e, ind, val);
        }

        tr[node] = min(tr[node*2], tr[(node*2)+1]);


}


int main()

{
        int n, q, i, in, va, left, right;
        scanf("%d%d", &n, &q);


        for(i=1; i<=n; i++){
            scanf("%d", &a[i]);
        }

         build(1, 1, n);

        for(i=1; i<=q; i++){
            cin>>b;
            if(b=="up"){
                scanf("%d%d", &in, &va);
                update(1, 1, n, in, va);
            }
            else{
                scanf("%d%d", &left, &right);
                int ans = query(1, 1, n, left, right);
                printf("Minimum element: %d\n", ans);
            }
        }

        return 0;
}