0分求助

#include <bits/stdc++.h>
using namespace std;
int main(){
	int s1,s2,s3,s4;
	cin>>s1>>s2>>s3>>s4;
	int a[s1+1],b[s2+1],c[s3+1],d[s4+1];
	for(int i=1;i<=s1;i++){
		cin>>a[i];
	} 
	for(int i=1;i<=s2;i++){
		cin>>b[i];
	} 
	for(int i=1;i<=s3;i++){
		cin>>c[i];
	} 
	for(int i=1;i<=s4;i++){
		cin>>d[i];
	}
	int num=0;
	for(int i=1;i<=s1;i++){
		if(i==s1){
			num+=a[i];
			a[i]=0;
		}
		else{			
			if(a[i]>a[i+1]) swap(a[i],a[i+1]);
			num+=a[i];
			a[i+1]=a[i+1]-a[i];
			a[i]=0;
		}
	}
	for(int i=1;i<=s2;i++){
		if(i==s2){
			num+=b[i];
			b[i]=0;
		}
		else{		
			if(b[i]>b[i+1]) swap(b[i],b[i+1]);
			num+=b[i];
			b[i+1]=b[i+1]-b[i];
			b[i]=0;
		}
	}
	for(int i=1;i<=s3;i++){
		if(i==s3){
			num+=c[i];
			c[i]=0;
		}
		else{		
			if(c[i]>c[i+1]) swap(c[i],c[i+1]);
			num+=c[i];
			c[i+1]=c[i+1]-c[i];
			c[i]=0;
		}
	}
	for(int i=1;i<=s4;i++){
		if(i==s4){
			num+=d[i];
			d[i]=0;
		}
		else{		
			if(d[i]>d[i+1]) swap(d[i],d[i+1]);
			num+=d[i];
			d[i+1]=d[i+1]-d[i];
			d[i]=0;
		}
	}
	cout<<num;
}