[Error] 'sum' was not declared in this scope; did you mean 'fsum'?报错

#include
#include
int fsum(int a[],int n){
for(int i=0;i
int sum;
sum+=a[i];
} return (sum);
}
int main(){
int a[1000];
int i,n,s;
scanf("%d",&n);
for(i=0;i
scanf("%d",&a[i]);
}s=fsum(a,n);
printf("%d",s);
return 0;
}
return（sum）报错[Error] 'sum' was not declared in this scope; did you mean 'fsum'?

把sum初始化为0，试一试 int sum=0