#include <stdio.h>

int main() {
    int x,y=0;
    scanf("%d %d",&x,&y);
    int x1,y1=0;
    scanf("%d %d",&x1,&y1);
    if(x1-x==1&&y1-y==0){
        printf("r");
    }if(x1-x==-1&&y1-y==0){
        printf("I");
    }if(x1-x==0&&y1-y==1){
        printf("u");
    }if(x1-x==0&&y1-y==-1){
        printf("d");
    }
    return 0;
}

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