CUBE-104: Tasty Chocolate

#include<stdio.h>
int const N = 1010;
int arr[N];
int n;

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

int dp[N][3010];

int cal(int i ,int b){
    if(b>3000)return 1e9;
    if(i > n){
        return 0;
    }
    if(dp[i][b] != -1)return dp[i][b];
    if(arr[i] <= b){
        return dp[i][b] = cal(i+1,b+1) + 1;
    }
    return dp[i][b] = min(cal(i+1,arr[i]) , cal(i+1,b+1) + 1);
}

int main()
{
    for(int i = 0 ; i < N ; i ++)for(int j = 0 ; j < 3010 ; j ++)dp[i][j] = -1;
    scanf("%d",&n);
    for(int i = 1 ; i <= n ; i ++){
        scanf("%d",&arr[i]);
    }
    printf("%d",cal(1,0));
    return 0;
}