矩阵的最短路径【C语言】

#include "stdio.h"
#include "stdlib.h"
#include "time.h"
void main()
{
    int m,n,i,j,t,min,a[30][30],b[30][30];
    char stw,stm[30][30];
    printf("Row:n:");
    scanf("%d",&n);
    printf("line m:");
    scanf("%d",&m);
    t=time(0)%1000;
    srand(t);
    printf("\n");
    for(i=1;i<=n;i++)
    {
        for(j=1;j<=m;j++)
        {
            a[i][j]=rand()%40+5;
            b[i][j]=a[i][j];
            printf("%4d",a[i][j]);
        }
        printf("\n");
    }
    for(j=m-1;j>=1;j--)
    {
        b[n][j]=b[n][j]+b[n][j+1];
        stm[n][j]=‘R‘;
    }
    for(i=n-1;i>=1;i--)
    {
        b[i][m]=b[i][m]+b[i+1][m];
        stm[i][m]=‘D‘;
    }
    for(i=n-1;i>=1;i--)
    for(j=m-1;j>=1;j--)
    {
        min=b[i+1][j+1];
        stm[i][j]=‘O‘;
        if(min>b[i+1][j])
        {
            min=b[i+1][j];
            stm[i][j]=‘D‘;
        }
        if(min>b[i][j+1])
        {
            min=b[i][j+1];
            stm[i][j]=‘R‘;
        }
        b[i][j]=b[i][j]+min;
    }
    printf("\n%d",b[1][1]);
    printf("\n %2d",a[1][1]);
    i=1;j=1;
    while(i<n || j<m)
    {
        stw=stm[i][j];
        if(stw==‘R‘)
        {
            j++;
            printf("-R-%d",a[i][j]);
        }
        else if(stw==‘D‘)
        {
            i++;
            printf("-D-%d",a[i][j]);
        }
        else
        {
            j++;
            i++;
            printf("-O-%d",a[i][j]);
        }
    }
}