2018D1T1 铺设道路(积木大赛)
problem&solution
贪心。没啥好说的。记得弄a[0].
code
#include <cstdio>
#include <algorithm>
#include <cmath>
#include <cstring>
#include <iostream>
using namespace std;
int read(){
int a=0,op=1;char c=getchar();
while(c>'9'||c<'0') {if(c=='-') op=-1;c=getchar();}
while(c>='0'&&c<='9'){a*=10,a+=c^48,c=getchar();}
return a*op;
}
int n,ans=0;
const int maxn=1e5+10;
int a[maxn];
int main(){
n=read();
for(int i=1;i<=n;i++) a[i]=read();
a[0]=0;
for(int i=1;i<=n;i++){
if(a[i]>a[i-1]) ans+=(a[i]-a[i-1]);
}
printf("%d",ans);
return 0;
}