挖坑和盖楼能一样么？！ ----题记

题目链接

code :

#include <iostream>
#include <stdio.h>
#include <string.h>
#include <algorithm>
#define maxn 100010
using namespace std ;
int ans , a[maxn] , n ;
int main () {
	//freopen ( "road.in" , "r" , stdin ) ;
	//freopen ( "road.out" , "w" , stdout) ;
	scanf("%d",&n) ; 
	for(int i = 1 ; i <= n ; i ++) {
		scanf("%d",&a[i]) ;
	}ans = a[1] ;
	for(int i = 2 ; i <= n ; i ++) {
		if(a[i] > a[i-1]) ans += a[i] - a[i-1] ; 
	}
	printf("%d\n",ans) ;
	return 0 ;  
}