{"problem":{"name":"Range Sums","description":{"content":"Takahashi has a secret integer sequence $a$. You know that the length of $a$ is $N$. You want to guess the contents of $a$. He has promised to give you the following $Q$ additional pieces of informati","description_type":"Markdown"},"platform":"AtCoder","limit":{"time_limit":2000,"memory_limit":262144},"difficulty":"None","is_remote":true,"is_sync":true,"sync_url":null,"sign":"abc238_e"},"statements":[{"statement_type":"Markdown","content":"Takahashi has a secret integer sequence $a$. You know that the length of $a$ is $N$.\nYou want to guess the contents of $a$. He has promised to give you the following $Q$ additional pieces of information.\n\n*   The $i$\\-th information: the value $a_{l_i}+a_{l_i+1}+\\cdots+a_{r_i}$.\n\nIs it possible to determine the sum of all elements in $a$, $a_1+a_2+\\cdots+a_N$, if the $Q$ pieces of promised information are given?\n\n## Constraints\n\n*   $1 \\leq N \\leq 2 \\times 10^5$\n*   $1 \\leq Q \\leq \\min(2 \\times 10^5,\\frac{N(N+1)}{2})$\n*   $1 \\leq l_i \\leq r_i \\leq N$\n*   $(l_i,r_i) \\neq (l_j,r_j)\\ (i \\neq j)$\n*   All values in input are integers.\n\n## Input\n\nInput is given from Standard Input in the following format:\n\n$N$ $Q$\n$l_1$ $r_1$\n$l_2$ $r_2$\n$\\hspace{0.4cm}\\vdots$\n$l_Q$ $r_Q$\n\n[samples]","is_translate":false,"language":"English"}],"meta":{"iden":"abc238_e","tags":[],"sample_group":[["3 3\n1 2\n2 3\n2 2","Yes\n\nFrom the first and second information, we can find the value $a_1+a_2+a_2+a_3$. By subtracting the value of $a_2$ from it, we can determine the value $a_1+a_2+a_3$."],["4 3\n1 3\n1 2\n2 3","No\n\nWe can determine the sum of the first $3$ elements of $a$, but not the sum of all elements."],["4 4\n1 1\n2 2\n3 3\n1 4","Yes\n\nThe fourth information directly gives us the sum of all elements."]],"created_at":"2026-03-03 11:01:14"}}