시간 제한메모리 제한제출정답맞힌 사람정답 비율
1 초 (추가 시간 없음) 1024 MB (추가 메모리 없음)50024818049.451%

문제

외계인 윤이는 지구를 정복하고자 세계의 중심 도시인 울산을 침략했다. 울산에는 $N$개의 빌딩이 일렬로 늘어서 있고, 왼쪽에서 $i$번째 건물의 높이는 $h_i$이다.

윤이는 울산을 파괴하기 위해 다음과 같은 계획을 세웠다. 윤이는 매일 UFO를 타고 울산의 상공을 가르며 가장 높이가 높은 빌딩에 레이저를 발사할 것이다. 레이저에 맞은 빌딩은 높이가 $1$ 낮아진다. 만약 그 날에 가장 높이가 높은 빌딩이 여러 개라면, 해당하는 모든 빌딩에 레이저를 발사한다. 만약 이미 모든 빌딩의 높이가 $0$이 되었다면, 윤이는 더 이상 레이저를 발사하지 않는다.

윤이는 지금까지 $D$일 동안 계획을 착실하게 수행해 왔다. 윤이가 $D$일 동안 레이저를 발사한 총 횟수를 구하시오.

입력

첫 번째 줄에 건물의 개수 $N$과 윤이가 계획을 수행한 날의 수 $D$가 공백으로 구분되어 주어진다. ($1\le N\le 300\ 000$, $1\le D\le 300\ 000$)

두 번째 줄에 건물의 높이를 나타내는 $N$개의 정수 $h_i$가 공백으로 구분되어 주어진다. ($1\le h_i\le 300\ 000$)

출력

윤이가 $D$일 동안 레이저를 발사한 총 횟수를 출력한다. (32비트 정수 범위를 넘을 수 있음에 유의하라.)

예제 입력 1

5 3
1 3 2 5 4

예제 출력 1

6
  • 처음 건물의 높이는 $[1,3,2,5,4]$이다.
  • 첫 번째 날에 윤이는 레이저를 $1$회 발사하며, 건물의 높이는 $[1,3,2,4,4]$가 된다.
  • 두 번째 날에 윤이는 레이저를 $2$회 발사하며, 건물의 높이는 $[1,3,2,3,3]$이 된다.
  • 세 번째 날에 윤이는 레이저를 $3$회 발사하며, 건물의 높이는 $[1,2,2,2,2]$가 된다.

 

예제 입력 2

5 2
1 1 1 1 1

예제 출력 2

5
  • 처음 건물의 높이는 $[1,1,1,1,1]$이다.
  • 첫 번째 날에 윤이는 레이저를 $5$회 발사하며, 건물의 높이는 $[0,0,0,0,0]$이 된다.
  • 두 번째 날에 이미 모든 건물의 높이가 $0$이므로 윤이는 레이저를 발사하지 않는다.
[{"problem_id":"26123","problem_lang":"0","title":"\uc678\uacc4 \uce68\ub7b5\uc790 \uc724\uc774","description":"<p>\uc678\uacc4\uc778 \uc724\uc774\ub294 \uc9c0\uad6c\ub97c \uc815\ubcf5\ud558\uace0\uc790 \uc138\uacc4\uc758 \uc911\uc2ec \ub3c4\uc2dc\uc778 \uc6b8\uc0b0\uc744 \uce68\ub7b5\ud588\ub2e4. \uc6b8\uc0b0\uc5d0\ub294 $N$\uac1c\uc758 \ube4c\ub529\uc774 \uc77c\ub82c\ub85c \ub298\uc5b4\uc11c \uc788\uace0, \uc67c\ucabd\uc5d0\uc11c $i$\ubc88\uc9f8 \uac74\ubb3c\uc758 \ub192\uc774\ub294 $h_i$\uc774\ub2e4.<\/p>\r\n\r\n<p>\uc724\uc774\ub294 \uc6b8\uc0b0\uc744 \ud30c\uad34\ud558\uae30 \uc704\ud574 \ub2e4\uc74c\uacfc \uac19\uc740 \uacc4\ud68d\uc744 \uc138\uc6e0\ub2e4. \uc724\uc774\ub294 \ub9e4\uc77c UFO\ub97c \ud0c0\uace0 \uc6b8\uc0b0\uc758 \uc0c1\uacf5\uc744 \uac00\ub974\uba70 \uac00\uc7a5 \ub192\uc774\uac00 \ub192\uc740 \ube4c\ub529\uc5d0 \ub808\uc774\uc800\ub97c \ubc1c\uc0ac\ud560 \uac83\uc774\ub2e4. \ub808\uc774\uc800\uc5d0 \ub9de\uc740 \ube4c\ub529\uc740 \ub192\uc774\uac00 $1$ \ub0ae\uc544\uc9c4\ub2e4. \ub9cc\uc57d \uadf8 \ub0a0\uc5d0 \uac00\uc7a5 \ub192\uc774\uac00 \ub192\uc740 \ube4c\ub529\uc774 \uc5ec\ub7ec \uac1c\ub77c\uba74, \ud574\ub2f9\ud558\ub294 \ubaa8\ub4e0 \ube4c\ub529\uc5d0 \ub808\uc774\uc800\ub97c \ubc1c\uc0ac\ud55c\ub2e4. \ub9cc\uc57d \uc774\ubbf8 \ubaa8\ub4e0 \ube4c\ub529\uc758 \ub192\uc774\uac00 $0$\uc774 \ub418\uc5c8\ub2e4\uba74, \uc724\uc774\ub294 \ub354 \uc774\uc0c1 \ub808\uc774\uc800\ub97c \ubc1c\uc0ac\ud558\uc9c0 \uc54a\ub294\ub2e4.<\/p>\r\n\r\n<p>\uc724\uc774\ub294 \uc9c0\uae08\uae4c\uc9c0 $D$\uc77c \ub3d9\uc548 \uacc4\ud68d\uc744 \ucc29\uc2e4\ud558\uac8c \uc218\ud589\ud574 \uc654\ub2e4. \uc724\uc774\uac00 $D$\uc77c \ub3d9\uc548 \ub808\uc774\uc800\ub97c \ubc1c\uc0ac\ud55c \ucd1d \ud69f\uc218\ub97c \uad6c\ud558\uc2dc\uc624.<\/p>\r\n","input":"<p>\uccab \ubc88\uc9f8 \uc904\uc5d0 \uac74\ubb3c\uc758 \uac1c\uc218 $N$\uacfc \uc724\uc774\uac00 \uacc4\ud68d\uc744 \uc218\ud589\ud55c \ub0a0\uc758 \uc218 $D$\uac00 \uacf5\ubc31\uc73c\ub85c \uad6c\ubd84\ub418\uc5b4 \uc8fc\uc5b4\uc9c4\ub2e4. ($1\\le N\\le 300\\ 000$, $1\\le D\\le 300\\ 000$)<\/p>\r\n\r\n<p>\ub450 \ubc88\uc9f8 \uc904\uc5d0 \uac74\ubb3c\uc758 \ub192\uc774\ub97c \ub098\ud0c0\ub0b4\ub294 $N$\uac1c\uc758 \uc815\uc218 $h_i$\uac00 \uacf5\ubc31\uc73c\ub85c \uad6c\ubd84\ub418\uc5b4 \uc8fc\uc5b4\uc9c4\ub2e4. ($1\\le h_i\\le 300\\ 000$)<\/p>\r\n","output":"<p>\uc724\uc774\uac00 $D$\uc77c \ub3d9\uc548 \ub808\uc774\uc800\ub97c \ubc1c\uc0ac\ud55c \ucd1d \ud69f\uc218\ub97c \ucd9c\ub825\ud55c\ub2e4. (32\ube44\ud2b8 \uc815\uc218 \ubc94\uc704\ub97c \ub118\uc744 \uc218 \uc788\uc74c\uc5d0 \uc720\uc758\ud558\ub77c.)<\/p>\r\n","hint":"","original":"1","html_title":"0","problem_lang_tcode":"Korean","sample_explain_1":"<ul>\r\n\t<li>\ucc98\uc74c \uac74\ubb3c\uc758 \ub192\uc774\ub294 $[1,3,2,5,4]$\uc774\ub2e4.<\/li>\r\n\t<li>\uccab \ubc88\uc9f8 \ub0a0\uc5d0 \uc724\uc774\ub294 \ub808\uc774\uc800\ub97c $1$\ud68c \ubc1c\uc0ac\ud558\uba70, \uac74\ubb3c\uc758 \ub192\uc774\ub294 $[1,3,2,4,4]$\uac00 \ub41c\ub2e4.<\/li>\r\n\t<li>\ub450 \ubc88\uc9f8 \ub0a0\uc5d0 \uc724\uc774\ub294 \ub808\uc774\uc800\ub97c $2$\ud68c \ubc1c\uc0ac\ud558\uba70, \uac74\ubb3c\uc758 \ub192\uc774\ub294 $[1,3,2,3,3]$\uc774 \ub41c\ub2e4.<\/li>\r\n\t<li>\uc138 \ubc88\uc9f8 \ub0a0\uc5d0 \uc724\uc774\ub294 \ub808\uc774\uc800\ub97c $3$\ud68c \ubc1c\uc0ac\ud558\uba70, \uac74\ubb3c\uc758 \ub192\uc774\ub294 $[1,2,2,2,2]$\uac00 \ub41c\ub2e4.<\/li>\r\n<\/ul>\r\n\r\n<p>&nbsp;<\/p>\r\n","sample_explain_2":"<ul>\r\n\t<li>\ucc98\uc74c \uac74\ubb3c\uc758 \ub192\uc774\ub294 $[1,1,1,1,1]$\uc774\ub2e4.<\/li>\r\n\t<li>\uccab \ubc88\uc9f8 \ub0a0\uc5d0 \uc724\uc774\ub294 \ub808\uc774\uc800\ub97c $5$\ud68c \ubc1c\uc0ac\ud558\uba70, \uac74\ubb3c\uc758 \ub192\uc774\ub294 $[0,0,0,0,0]$\uc774 \ub41c\ub2e4.<\/li>\r\n\t<li>\ub450 \ubc88\uc9f8 \ub0a0\uc5d0 \uc774\ubbf8 \ubaa8\ub4e0 \uac74\ubb3c\uc758 \ub192\uc774\uac00 $0$\uc774\ubbc0\ub85c \uc724\uc774\ub294 \ub808\uc774\uc800\ub97c \ubc1c\uc0ac\ud558\uc9c0 \uc54a\ub294\ub2e4.<\/li>\r\n<\/ul>\r\n"},{"problem_id":"26123","problem_lang":"1","title":"Yunee the Alien Invader","description":"<p>Yunee the alien is invading Ulsan, the world&rsquo;s central city, to conquer the Earth. There are $N$ buildings in a row in Ulsan, and the height of the $i$-th building from the left is $h_i$.<\/p>\r\n\r\n<p>Yunee made the following plan to destroy Ulsan. Every day, Yunee will ride a UFO to fly through the sky over Ulsan, and fire lasers at the tallest buildings. Buildings hit by the laser lose $1$ in height. If there are multiple tallest buildings on that day, Yunee will fire lasers at all of them. If all the buildings are already $0$ in height, Yunee will not fire any more lasers.<\/p>\r\n\r\n<p>Yunee has been carrying out the plan for $D$ days so far. Find the total number of times Yunee fired the laser for $D$ days.<\/p>\r\n","input":"<p>In the first line, the number of buildings $N$ and the number of days $D$ are given, separated by whitespace. ($1\\le N\\le 300\\ 000$, $1\\le D\\le 300\\ 000$)<\/p>\r\n\r\n<p>The second line gives $N$ integers $h_i$ representing the building heights. ($1\\le h_i\\le 300\\ 000$)<\/p>\r\n","output":"<p>Print the total number of times Yunee fired the laser for $D$ days. (Note that it can exceed the range of 32-bit integer type.)<\/p>\r\n","hint":"","original":"0","html_title":"0","problem_lang_tcode":"English","sample_explain_1":"<ul>\r\n\t<li>The initial building heights are $[1,3,2,5,4]$.<\/li>\r\n\t<li>On day 1, Yunee fires the laser $1$ times, and the building heights become $[1,3,2,4,4]$.<\/li>\r\n\t<li>On day 2, Yunee fires the laser $2$ times, and the building heights become $[1,3,2,3,3]$.<\/li>\r\n\t<li>On day 3, Yunee fires the laser $3$ times, and the building heights become $[1,2,2,2,2]$.<\/li>\r\n<\/ul>\r\n","sample_explain_2":"<ul>\r\n\t<li>The initial building heights are $[1,1,1,1,1]$.<\/li>\r\n\t<li>On day 1, Yunee fires the laser $5$ times, and the building heights become $[0,0,0,0,0]$.<\/li>\r\n\t<li>On day 2, Yunee no longer fires the laser because the building heights are already $0$.&nbsp;<\/li>\r\n<\/ul>\r\n"}]