[CF 295A] Grag and Array [differential sequence]

Question:

There are Series a []; Operation op [] = {l, r, d}; ask q [] = {x, y };

The operation adds d to each number in the [l, r] interval of a. the query indicates executing op between [x, y.

Print the final sequence.

Ideas:

Two differential columns are used to process the number of calls made to each op and then perform operations on the sequence.

 

#include <cstdio>#include <cstring>#include <algorithm>using namespace std;const int MAXN = 1e5+5;typedef long long ll;ll a[MAXN],sum[MAXN];ll d[MAXN],delta[MAXN];int l[MAXN],r[MAXN];int main(){    int n,m,k;    scanf("%d %d %d",&n,&m,&k);    for(int i=1;i<=n;i++)        scanf("%I64d",a+i);    for(int i=1;i<=m;i++)        scanf("%d %d %I64d",l+i,r+i,delta+i);    int x,y;    while(k--)    {        scanf("%d %d",&x,&y);        d[x]++;d[y+1]--;    }    for(int i=1;i<=m;i++)    {        sum[i] = sum[i-1] + d[i];        delta[i] *= sum[i];    }    memset(d,0,sizeof(d));    memset(sum,0,sizeof(sum));    for(int i=1;i<=m;i++)    {        if(!delta[i])    continue;        d[l[i]] += delta[i];        d[r[i]+1] -= delta[i];    }    for(int i=1;i<=n;i++)    {        sum[i] = sum[i-1] + d[i];        a[i] += sum[i];        printf("%I64d%c",a[i],i==n?'\n':' ');    }}