Problem p00033 (C++) — buggy submission, verdict: Time Limit Exceeded

#include <stdio.h>
int main() {
  int a;
  scanf("%d", &a);
  while (a--) {
    int b, flag = 1;
    int right = 0, left = 0;
    for (int i = 0; i < 10; i++) {
      scanf("%d", &b);
      if (b > right) {
        right = b;
        continue;
      }
      if (b > left) {
        left = b;
        continue;
      }
      if (flag)
        printf("NO\\n");
      flag = 0;
    }
    if (flag)
      printf("YES\\n");
  }
  return 0;
}

Error: TLE

Fixed submission:

#include <iostream>
using namespace std;

//?目中?出的最大?度和高度
#define MAX_W 20
#define MAX_H 20

// 待?入的?度和高度以及已走的?数
int W, H;
int step = 0;
int minStep;
int sRow, sCol;

// 待写入的二?数?
int room[MAX_W][MAX_H];

//???的可走方向
const int direc[4][2] = {
    {0, -1},
    {1, 0},
    {0, 1},
    {-1, 0},
};

void dfs(const int &row, const int &col, int step) {
  if (step >= 10 || step > minStep) {
    return;
  }

  for (int d = 0; d < 4; ++d) {
    int cRow = row;
    int cCol = col;

    while (cRow >= 0 && cRow < H && cCol >= 0 && cCol < W) {
      switch (room[cRow][cCol]) {
      case 0: {
        cRow += direc[d][1];
        cCol += direc[d][0];
        break;
      }

      case 3: {
        if (step + 1 < minStep) {
          minStep = step + 1;
        }
        cRow = -1;
        break;
      }

      case 1: {
        if (!(cRow - direc[d][1] == row && cCol - direc[d][0] == col)) {
          room[cRow][cCol] = 0;
          dfs(cRow - direc[d][1], cCol - direc[d][0], step + 1);
          room[cRow][cCol] = 1;
        }

        cRow = -1;
        break;
      }

      default: {
        break;
      }
      }
    }
  }
}

int main() {
  while (cin >> W >> H, W > 0) {
    //?入
    for (int row = 0; row < H; ++row) {
      for (int col = 0; col < W; ++col) {
        cin >> room[row][col];
      }
    }

    //?2的点?起始点
    for (int row = 0; row < H; ++row) {
      for (int col = 0; col < W; ++col) {
        if (room[row][col] == 2) {
          sRow = row;
          sCol = col;
          break;
        }
      }
    }

    room[sRow][sCol] = 0;
    minStep = 11;
    dfs(sRow, sCol, 0);

    if (minStep > 10) {
      minStep = -1;
    }

    //?出?果
    cout << minStep << endl;
  }
}

/*
??附?：
POJ 3009 Curling 2.0
On Planet MM-21, after their Olympic games this year, curling is getting
popular. But the rules are somewhat different from ours. The game is played on
an ice game board on which a square mesh is marked. They use only a single
stone. The purpose of the game is to lead the stone from the start to the goal
with the minimum number of moves.

Fig. 1 shows an example of a game board. Some squares may be occupied with
blocks. There are two special squares namely the start and the goal, which are
not occupied with blocks. (These two squares are distinct.) Once the stone
begins to move, it will proceed until it hits a block. In order to bring the
stone to the goal, you may have to stop the stone by hitting it against a block,
and throw again.


Fig. 1: Example of board (S: start, G: goal)

The movement of the stone obeys the following rules:

At the beginning, the stone stands still at the start square.
The movements of the stone are restricted to x and y directions. Diagonal moves
are prohibited. When the stone stands still, you can make it moving by throwing
it. You may throw it to any direction unless it is blocked immediately(Fig.
2(a)). Once thrown, the stone keeps moving to the same direction until one of
the following occurs: The stone hits a block (Fig. 2(b), (c)). The stone stops
at the square next to the block it hit. The block disappears. The stone gets out
of the board. The game ends in failure. The stone reaches the goal square. The
stone stops there and the game ends in success. You cannot throw the stone more
than 10 times in a game. If the stone does not reach the goal in 10 moves, the
game ends in failure.

Fig. 2: Stone movements

Under the rules, we would like to know whether the stone at the start can reach
the goal and, if yes, the minimum number of moves required.

With the initial configuration shown in Fig. 1, 4 moves are required to bring
the stone from the start to the goal. The route is shown in Fig. 3(a). Notice
when the stone reaches the goal, the board configuration has changed as in Fig.
3(b).


Fig. 3: The solution for Fig. D-1 and the final board configuration

?入
The input is a sequence of datasets. The end of the input is indicated by a line
containing two zeros separated by a space. The number of datasets never exceeds
100.

Each dataset is formatted as follows.

the width(=w) and the height(=h) of the board
First row of the board
...
h-th row of the board
The width and the height of the board satisfy: 2 <= w <= 20, 1 <= h <= 20.

Each line consists of w decimal numbers delimited by a space. The number
describes the status of the corresponding square.

0   vacant square
1   block
2   start position
3   goal position
The dataset for Fig. D-1 is as follows:

6 6
1 0 0 2 1 0
1 1 0 0 0 0
0 0 0 0 0 3
0 0 0 0 0 0
1 0 0 0 0 1
0 1 1 1 1 1

?出
For each dataset, print a line having a decimal integer indicating the minimum
number of moves along a route from the start to the goal. If there are no such
routes, print -1 instead. Each line should not have any character other than
this number.

?例?入
2 1
3 2
6 6
1 0 0 2 1 0
1 1 0 0 0 0
0 0 0 0 0 3
0 0 0 0 0 0
1 0 0 0 0 1
0 1 1 1 1 1
6 1
1 1 2 1 1 3
6 1
1 0 2 1 1 3
12 1
2 0 1 1 1 1 1 1 1 1 1 3
13 1
2 0 1 1 1 1 1 1 1 1 1 1 3
0 0

?例?出
1
4
-1
4
10
-1
*/