Truck Tour

                            Solution in C :

In C ++ :





#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;

int n, p[100005], d[100005];
int main() {
    scanf("%d", &n);
    for (int i = 0; i < n; ++i) scanf("%d%d", &p[i], &d[i]);
    int ret = 0, amount = 0, sum = 0;
    for (int i = 0; i < n; ++i) {
        p[i] -= d[i];
        sum += p[i];
        if (amount + p[i] < 0) {
            amount = 0;
            ret = i + 1;
        } else amount += p[i];
    }
    printf("%d\n", sum >= 0 ? ret : -1);
    return 0;
}








In Java :





import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {
	public static void main(String [] args) {
		Scanner in = new Scanner(System.in);
		int n = in.nextInt();
		List<Integer> list = new ArrayList<Integer>();
		int tank = 0;
		int result = -1;
		for(int loop=0; loop<n; loop++) {
			int net = in.nextInt() - in.nextInt();
			if(tank + net > 0) {
				if(result==-1) {
					result = loop;
				}
				list.add(net);
				tank += net;
			} else {
				list.clear();
				tank = 0;
				result = -1;
			}
		}
		System.out.println(result);
		in.close();
	}
}








In C :






#include <stdio.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>

int main() {
    int n, a[100000][2], i, j, k;
    long int tot;
    scanf("%d", &n);
    for(i=0; i < n; i++)
        scanf("%d%d", &a[i][0], &a[i][1]);
    for(i = 0; i < n; i++) {
        j = i;
        k = n;
        tot = 0;
        while (k--) {
            tot += a[j][0];
          //  printf("## %d %d\n", tot, a[j][1]);
            if (tot < a[j][1])
                break;
            tot -= a[j][1];
            j ++;
            if (j == n)
                j = 0;
        }
        //printf("%d\n", k);
        if (k == -1) {
            printf("%d", j);
            break;
        }
        
    }
        
    
    return 0;
}








In Python3 :





num=int(input())
pet=[]
dist=[]
for line in range(num):
    i=input().split(" ")
    pet.append(int(i[0]))
    dist.append(int(i[1]))
bal=[]
for i in range(num):
    bal.append(pet[i]-dist[i])

small=0    
for strt in range(num):
    s=bal[strt]
    i=(strt+1)%num
    while(s>=0 and i!=strt): 
        s+=bal[i]    
        i=(i+1)%num
    if(i==strt):
        small=strt
        break
        
print(small)