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  1. #include<bits/stdc++.h>
  2. using namespace std;
  3. #define endl '\n'
  4. #define int long long int
  5. const int MOD = 1000000007;
  6. const int MOD2 = 998244353;
  7. const int INF = LLONG_MAX / 2;
  8. const int MAXN = 100000;
  9. int primes[1000000];
  10.  
  11. /*void seive() {
  12.   fill(primes, primes + 1000000, 1);
  13.   primes[0] = primes[1] = 0;
  14.   for (int i = 2; i * i < 1000000; i++) {
  15.   if (primes[i]) {
  16.   for (int j = i * i; j < 1000000; j += i) {
  17.   primes[j] = 0;
  18.   }
  19.   }
  20.   }
  21. }
  22.  
  23. bool isPrime(int n) {
  24.   if (n <= 1) return false;
  25.   for (int i = 2; i * i <= n; i++) {
  26.   if (n % i == 0) return false;
  27.   }
  28.   return true;
  29. }
  30.  
  31. int gcd(int a, int b) {
  32.   if (a == 0) return b;
  33.   return gcd(b % a, a);
  34. }
  35.  
  36. int power(int a, int b, int mod) {
  37.   int res = 1;
  38.   a %= mod;
  39.   while (b > 0) {
  40.   if (b & 1) res = res * a % mod;
  41.   a = a * a % mod;
  42.   b >>= 1;
  43.   }
  44.   return res;
  45. }
  46.  
  47. // nCr % MOD for n < MOD
  48. int nCrModP(int n, int r) {
  49.   if (r > n) return 0;
  50.   if (r == 0 || r == n) return 1;
  51.  
  52.   int numerator = 1, denominator = 1;
  53.   for (int i = 0; i < r; i++) {
  54.   numerator = (numerator * (n - i)) % MOD;
  55.   denominator = (denominator * (i + 1)) % MOD;
  56.   }
  57.   return (numerator * power(denominator, MOD - 2, MOD)) % MOD;
  58. }
  59.  
  60. // Lucas's Theorem
  61. int lucas(int n, int r) {
  62.   if (r == 0) return 1;
  63.   return (lucas(n / MOD, r / MOD) * nCrModP(n % MOD, r % MOD)) % MOD;
  64. }*/
  65. void solve() {
  66. int n;
  67. cin>>n;
  68. int A[n];
  69. int total = 0;
  70. for(int i = 0 ; i<n ; i++){
  71. cin>>A[i];
  72. total += A[i];
  73. }
  74. int p4[n],p2[n];
  75. p4[n-1] = A[n-1];
  76. int sum = A[n-1];
  77. for(int i = n-2 ; i>=0 ; i--){
  78. sum += A[i];
  79. p4[i] = min((p4[i+1]),sum);
  80. }
  81. sum = 0;
  82. for(int i = 0 ; i<n ; i++){
  83. p2[i] = min(A[i],(sum+A[i]));
  84. }
  85. int ans = LLONG_MAX;
  86. ans = min(p2[n-1],p4[0]);
  87. for(int i = 0 ; i<n-1 ; i++){
  88. int d = min(0LL,p2[i])+min(0LL,p4[i+1]);
  89. ans = min(ans,d);
  90. }
  91. cout<<total-(2*ans)<<endl;
  92. }
  93. signed main() {
  94. ios::sync_with_stdio(false); cin.tie(NULL);
  95. int t;
  96. cin >> t;
  97. while (t--) {
  98. solve();
  99. }
  100. return 0;
  101. }
  102.  
Success #stdin #stdout 0.01s 5288KB
stdin
2
4
1 2 1 -5
3
-4 1 -1
stdout
9
6