Untitled

#include <stdio.h>
int n, m;
int i, j, k;
char in[45][45] = {'\0'}, out[45][45] = {'\0'};
int main(void) {
    int flag = 0;
    scanf("%d %d", &n, &m);
    for (i = 0; i < n; i++) {
        for (j = 0; j < m; j++) {
            scanf(" %c", &in[i][j]);
            out[i][j] = in[i][j];
        }
    }
    int temp = 0, steps = 45;
    for (j = 0; j < m; j++) {
        flag = 0;
        for (i = n - 1; i >= 0 && flag == 0; i--) {
            temp = 0;
            if (in[i][j] == 'o') {
                flag = 1;
                if (i == n - 1)
                    steps = 0;
                else {
                    for (k = i + 1; k < n; k++) {
                        if (in[k][j] == 'x' && k == i + 1) {
                            steps = 0;
                            break;
                        }
                        if (in[k][j] == '.')
                            temp++;
                        else
                            break;
                    }
                }
                if (temp < steps && temp != 0) steps = temp;
            }
        }
    }
    /* for (i = 0; i < n; i++) {  //算掉下來幾步
        for (j = 0; j < m; j++) {
            temp = 0;
            if (in[i][j] == 'o') {
                for (k = (i + 1); k < n; k++) {
                    if (in[k][j] == '.') {
                        temp++;
                    } else {
                        break;
                    }
                }
                if (temp < steps && temp != 0) steps = temp;
                break;
            }
        }
    } */

    for (i = 0; i < n; i++) {  //掉下來然後變成x
        for (j = 0; j < m; j++) {
            if (in[i][j] == 'o') {
                out[i][j] = '.';
                out[i + steps][j] = 'x';
            }
        }
    }

    for (i = (n - 1); i >= 0; i--) {  //刪掉滿的行
        temp = 0;
        for (j = 0; j < m; j++) {
            if (out[i][j] != '.') {
                temp++;
                if (temp == m) {
                    for (k = 0; k < m; k++) {
                        out[i][k] = '.';
                    }
                }
            } else
                break;
        }
    }
    /* for (i = 0; i < n; i++) {
        for (j = 0; j < m; j++) {
            printf("%c", out[i][j]);
        }
        printf("\n");
    } */

    temp = 0;
    for (i = (n - 1); i >= 0; i--) {
        flag = 0;
        for (j = 0; j < m; j++) {
            if (out[i][j] != '.') {
                flag = 1;
                break;
            }
        }
        if (flag == 1 && i < n - 1 - temp) {
            for (j = 0; j < m; j++) {
                out[n - 1 - temp][j] = out[i][j];
                if (n - 1 - temp != i) out[i][j] = '.';
            }
        }
        if (flag == 1) temp++;
    }

    for (i = 0; i < n; i++) {
        for (j = 0; j < m; j++) {
            printf("%c", out[i][j]);
        }
        printf("\n");
    }

    return 0;
}

/* 
# Sample Input 1
8 9
..o......
.oo......
..o......
.........
.........
x..xxxxxx
x..xxxxxx
xx.xxxxxx

# Sample Input 2
11 9
..o......
..o......
..o......
..o......
.........
.........
.........
xx.xxxxxx
xx.xxx.xx
x..xxxxxx
xx.xxxxxx

11 9
..o......
..o......
..o......
..o......
.........
.........
.........
xx.xxx.xx
xx.xxxxxx
x..xxxxxx
xx.xxxxxx

11 9
..o......
..o......
..o......
..o......
..o......
..o......
..o......
xxoxxxxxx
xxoxxx.xx
x.oxxxxxx
xxoxxxxxx

# Sample Input 3
8 7
.......
...oo..
..oo...
..o....
.......
.x.....
xx.xxxx
x.xxxxx

8 7
.......
.x.oo..
.xoo...
.xo....
.x.....
.x.....
xx.xxxx
x.xxxxx

8 7
.......
.xxxx..
.xoo...
.xo....
.x.....
.x.....
xx.xxxx
x.xxxxx

 */