About the bubble sort in c

This is my code: //buble sort

#include<stdio.h>
int main(){
    int a[11];
    int temp;
    int i,j;
//input

for(i=1;i<=10;i++){
    scanf("%d",&a[i]);
}

//sort

for(i=1;i<10;i++){  //the number of number
    for(j=1;j<10-i;j++) //--
        if(a[j]<a[j+i]){
            temp=a[j];
            a[j]=a[j+1];
            a[j+1]=temp;
        }
}

//output
for(i=1;i<=10;i++){
    printf("%d ",a[i]);
}

getchar();
getchar();
return 0;

}

but the result was not like what I think.the number before was 1 2 3 4 5 6 7 8 9 0 but after it was 8 6 5 4 3 7 2 9 1 0 thanks !